Sensory Deprivation

The UK is heading for an energy crisis in which we become over reliant on imported natural gas for our home heating and power generation. Of the 27 EU countries, the UK has the largest gas consumption of close to 100 billion cubic metres (bcm) per year. By 2015 as a result of changes in the UK electricity generating mix is going to further increase the percentage share of gas used for generating, as coal and nuclear stations reach end of life. Our gas consumption is set to rise to 120 bcm. Unless the UK can maintain a secure supply of natural gas, from friendly nations, we are heading for an almighty energy crisis.

Currently about 35% of UK gas consumption is for domestic heating. Much of our housing stock offers such poor energy efficiency that we are literally throwing away billions in our gas bills every year. The new coalition government have been advised of this and are targeting the domestic sector to reduce their energy consumption by way of better energy efficiency in the home - such as improved insulation and more efficient boilers.

In the next 40 year time frame there will be co-ordinated effort to improve the energy efficiency of our housing stock. 60% of our homes were built before 1960 and have very poor efficiency. National programmes to roll out internal and external insulation will bring our homes up to a better standard. This will help maintain gas consumption at 2010 levels, and keep our national CO2 footprint to a minimum.

Part of the problem is that older UK homes leak heat like a seive. Solid brick walls and uninsulated lofts mean that we are using at least 3 times the energy than we need to. Clearly something has to be done to curb these energy losses.

First it is important to quantify the energy consumption and losses in the older property. As part of my personal effort, I have been monitoring gas usage in my home for nearly 10 years, and noting year on year improvements.

Part of the problem is to understand the energy usage and where the heat losses occur. For this I have been working on a temperature and energy monitoring system.

In the last couple of days, I have put together a simple Arduino temperature sensing application which sends readings up to Pachube for logging and graphing.

A mental block, last weekend prevented me from converting the readings from the thermistor temperature sensors to a true centigrade reading, but in the cool light of Friday morning, I revisited the code and got the thermistor linearisation code working.

The results can be seen at my Pachube feed - I'm looking at a couple of room temperatures, the temperature at two points of my hot water tank and the outside temperature.

The standard Arduino has 6 analogue sensing channels (the Nano has an additional two ADC channels). By using Dallas 1-wire temperature sensors connected to digital pins, a much larger network of temperature sensors is possible.

At the moment, I'm monitoring my hot water tank temperature - solely becase it shows a wide range of temperature swing, which is good for testing. It would also be beneficial to monitor the inlet and exit temperatures of my solar water heating panel and in the heating season, the boiler and woodstove temperatures. Each room of the house could be individually monitored including the loft, to give a complete picture of the thermal behaviour of the house

More Messaging

Below are some jottings and thoughts I wrote down on 13th July. Just about 5 weeks later (starting new job etc) - most of these ideas are coming to fruition. The idea of communicating between ethernet enabled microcontrollers using Pachube as a message broker is currently being pursued.

Getting small microcontroller systems to talk to the web is an area of increasing interest. With many homeowners now possessing "always-on" broadband routers, the task of getting home automation, sensing and security systems online has never been easier or cheaper.

In this interesting talk/slide show, "The House That Twitters", Andy Stanford-Clark, describes how he has arranged devices around his house to publish data using MQTT to a Really Small Message Broker (RSMB) and then make that data to other subscribing devices. As Andy invented and subsequently developed MQTT, it is fitting that he choses to use his own house as an example of what can be done. He also explained that once he had established the basic system, then new devices and applications could be added relatively easily without having to start from scratch each time.

My aspirations are somewhat different, and perhaps much cruder. My aim is to get stand-alone Arduinos to exchange data with each other using Pachube as the message broker.

With a little help from others, I now have analogue readings from my Arduino appearing as a Pachube feed. The next task is to retrieve the data from that feed using another Arduino and make use of it, for example display it on a local LCD, or have the second Arduino parse through the data, and make control decisions based on the numeric values of the data. Here Pachube would be acting solely as a message broker - receiving data from the first Arduino which is the publisher, and making it available to any other Arduino which wishes to subscribe to it. It is this Publisher/Subscriber relationship (PubSub) which is key to any message brokerage system.

For this to work, the subscribing Arduino(s) must have a means of accessing the raw csv data on Pachube, using the GET method. I'm still reading up on this and am yet to find an example which explains it in simple terms. I'm hoping to reach the point where the whole PubSub functionality is handled in underlying code, and all the Arduino user needs to do is read from or write to a suitably sized buffer.

Messaging between Arduinos, or other small micros, should be made as simple as texting your mates.

All you need is a feed number on Pachube to send the data to, and the subscribing Arduinos regularly look for updates. The subscribers might just display the data on an LCD for example, or use the various fields for specific control purposes. One field might be a bit pattern that you want to send to an output port and control a bunch of relays, another field might be the unique address of a specific Arduino that you want to send a command to. If the message length was kept to 128 bytes then this should be small enough to allow easy manipulation on the Arduino, be compatible with Twitter, and provide sufficient scope for several fields to reflect analogue values, bit maps for port setting and various other control structures.

Hardware Thoughts.

Hardware needs to be cheap and cheerful with much of the elegance of the application provided in the firmware.

What is needed in terms of hardware to give a microcontroller access to web connectivity? What are the opportunities for a low cost, open source hardware solution?

First what is needed is a network interface controller - a NIC chip. Microchip offer the low cost ENC28J60 which is available for about £2. With a RJ45 jack, with integrated magnetics - a mag-jack, a 25MHz crystal and a few other components you can put together a simple 10Mbit ethernet controller.

Alternatively, if you are working with the popular Arduino microcontroller, then you can buy a ready built and tested ethernet shield which uses the ENC28J60, for as little as £12.50. This little board comes with example sketches, and others have developed and improved upon these to make connection to Twitter and Pachube relatively straight forward.

Now one of the problems of ethernet and web access is the hosting of the TCP/IP stack, which tends to put a large burden on the resource limited microcontroller, in terms of RAM and program code size. This leaves little available for the application - which may be a problem. Indeed the ethernet shield with the ENC28J60 is limited in application when compared to the Wiznet W5100 based "Official" Ethernet Shield- but that costs twice the price!

However with the availability of the 32K ATmega328 microcontroller, now fitted to most new Arduinos, the problem is somewhat reduced.

Other options include a combination of ATmega328 and ENC28J60 on one simple pcb which have recently appeared - such as this one from Tuxgraphics who also provide a handy tutorial on their cut down TCP/IP stack specifically for AT mega microcontrollers. Tuxgraphics have been developing AVR/ENC28J60 applications for several years, and are a useful source of information - should you wish to follow this particular hardware combination.

Message in a Bottle

The Smart Heating Controller took a step further today with the addition of an ethernet shield from NuElectronics. I bought this back in 2008 but it took some aspiration and some updated code from Andrew Lindsay in order to get it to work.

The Arduino measures the temperature from six analogue thermistor channels and then PUTs them up to Pachube in a CSV format - but you can also browse them locally or remotely at the IP address of your router.

The readings are updated to the net about every 10 seconds, whilst the LCD is refreshed every second. The LCD shows the time, the 6 temperature readings and whether the circulation pump is on or off.

The rather scruffy breadboard below the Arduino terminates the cables to the thermistors - which are about 10m away. It also holds the potentiometer for setting the set-point temperature and the 433MHz wireless module for turning the boiler on and off.

I'm still trying to get the device to work reliably with Pachube. It showed signs of promise this afternoon, briefly PUTting data up to a Pachube feed, but when I integrated my LCD code, I have clearly introduced a bug to the overall program. After some serious back-tracking its now working correctly on Pachube Feed 8729

Personally, I've found the whole web client business a bit of a ball-ache, possibly because I'm a C newbie plus the fact that I'm unfamiliar with the methods involved. There has to be an easier method to get small low cost microcontroller systems to send messages to one another.

I've been thinking about how microcontrollers could communicate with one another efficiently, with low resource overhead, across a variety of communications links - ethernet/internet, wired and wireless networks.

I recently came across the MQTT messaging system developed by Andy Stanford-Clark and his team at IBM Labs, Hursley. Andy has demonstrated MQTT in his automated home and has a number of interesting applications - as described in this video.

Nick O'Leary, also at IBM, has developed a MQTT Client for the Arduino

To make use of MQTT you need to run a message broker application such as Really Small Message Broker RSMB - and in this document, Mark E. Taylor describes the end to end implementation of a network connected temperture sensor, using an Arduino with the RSMB running on a Linux machine.

RSMB is a proprietary IBM product, but there is at least one open source alternative - such as mosquitto by Roger Light.

Hopefully it will achieve momentum amongst the hacking community as an efficient way of messaging between low cost micros and other applications including Twitter etc.

The Heat is On!

Here's a challenge. Teach yourself C in 21 days!

The book on the left runs to 700 pages. I borrowed it 10 years ago from a mate, and now just getting around to studying it!

Learning C from a text book is somewhat dull, but with hands-on and near instant results using the Arduino - it makes the whole process a lot easier and more interesting - especially if you have an application waiting.

So whilst my code is a little clunky, and having never been taught good programming practice (we were taught FORTRAN 77 for a year at Uni in 1983, whilst the year above us learned ALGOL 68!!), I am still learning quite a few of the basics, and trying to make the journey and transition from being confined byPIC assembly language.

This morning I learnt the structure of arrays and how to index into them with a pointer. Whilst I have been using this construct for years in PIC code to send messages - today was my first time in C. I can now send all sorts of serial messages to devices using a modified bit-banging serial routine.

As an update to my Arduino base central heating control system outlined in the previous post I have now got the wireless boiler commands working and combined the sketch with the temperature controller sketch I wrote at the end of June to read 6 thermistor channels and display the temperatures on an LCD display.

My boiler is now turning on and off under Arduino control. Like I said earlier - just enough knowledge of C to be dangerous.

The plan now is to integrate this application with Andrew Lindsay's modified ethernet code for the NuElectronics ENC28J60 ethernet shield. The intention is to get the readings of the six sensors up to Pachube. The NuElectronics shield has not proven so popular as other ethernet shields, as it relies on the ATmega to host a cut down TCP/IP stack. This can be troublesome on the mega168, but with Andy's code improvements it should run better on the mega328 which has double the codespace and double the RAM.

Smarter Heating Control?

Central heating control systems historically tend to be incredibly simple, responding to a single, often badly located thermostat, and a time of day timer, which is often out of kilter with the hours we actually need the heating to be effective.

Using low cost, open source hardware, can we improve on the levels of control and make significant savings to the amount of energy we use heating our homes?

About 6 months ago in January, when we were up to our knees in snow, I started thinking about how our simple central heating systems could be modified to make them more efficient and to use less gas.

We have all strived to reduce our electricity consumption - by turning off unnecessary equipment, but with gas heating, we could be wasting hundreds of kWh and not even realising it.

Before I dive into more sophisticated electronic controls - I will point out that improved insulation and draughtproofing will always offer the most cost effective reduction in domestic heating fuel usage.

The extent to which we heat our houses is entirely subjective depending on our personal level of comfort and the house occupancy, which is a function of lifestyle. For example, a modern well insulated home occupied by a professional couple might need to run the heating for two hours in the early morning and a few hours in the evening, whilst for someone working from home, or at home with a young family might need constant background heating.

The first thing to do is to measure the existing usage, in terms of time of day, internal temperatures needed for comfort and absolute gas consumption, and relate these to the average outside temperatures.

In order to make use of low cost open source hardware, I have chosen the Arduino to form the basis of my home heating monitoring system. As well as low cost, it is easy to interface to, relatively easy to program and benefits from the vast experience of a very large user base. With the use of a series of expansion shields, such as the ethernet shield and the Real Time Clock/sensor/SDcard shield, it becomes a useful cost effective tool for on line, real time datalogging. It can function as a standalone system - without the need of a PC or laptop in attendance.

So what parts of this project are already in place? The following list are those that have already been achieved by various enthusiasts (plus myself), or arisen from suggestions from others in the HomeCamp Community.

1. Measuring the temperature across several rooms.

The standard Arduino has 6 analogue input channels. These can be readily used to read low cost thermistor temperature sensors. A few lines of code running on the Arduino, linearises and scales the output of the thermistor to give a temperature reading in degrees centigrade. You can also use pipeclip thermistors to monitor the temperature of points on your hot water cylinder so you can decide whether it it hot enough to bath or shower.

2. Tracking the outside temperature - weather compensation.

By measuring the outside temperature - particularly in the very early hours of the morning, it is possible to predict how much heat is likely to be needed to bring the house up to a comfortable temperature when the occupants awaken. Older, less well insulated houses lose more heat to the environment. Knowing this rate of heat loss - which is proportional to the temperature difference between inside and outside allows you to better predict how much gas heating you will need. As comfort is very much a lifestyle choice, if you have alternative heating, such as a multifuel stove, you may choose to use this in preference to gas - at weekends for example, to offset the gas consumption.

3. Historical records of daily average outside temperatures.

A historical archive of daily average temperatures is available online for many towns across the UK. This record could be coded into the Arduino as a look up table, so that it could make a prediction to how much heating is likely to be needed on a particular day. Based on the early morning temperature, the historical average, and whether it is a weekend, your heating control system might choose a different strategy than if it were a milder weekday - for instance.

4. Measuring gas consumption on an Arduino and outputing it in CurrentCost XML format to display on Dale Lane's GUI (and others).

An earlier post to this blog showed how it was possible to read the gas consumption from a gas meter by using a non-contact optical sensing method. The pulse count data, relating to gas consumption can be converted into an XML message format similar to that output by the Current Cost electricity monitor, and passed out via a serial connection to be logged and graphed on a PC. As an example of a third party application for graphing and logging - I chose Dale Lane's GUI.

As an aside, Current Cost have sold 1.126 million energy monitors, and are introducing new products to give access to internet connectivity. The "10 channel" display capability of the Current Cost Envi could be used to monitor additional household data - such as solar water heating, pV or anything else.

5. Determining the heat-up, cool down curves for the particular property.

For a given average outside temperature, heat loss from a property will be at a certain rate. By determining this rate, it is possible to calculate the amount of heat needed to warm a property up from cold to the comfort temperature, and this can be converted to the required boiler on-time.

6. Wireless control of the boiler using a hacked wireless thermostat protocol.

Some years ago I deciphered the wireless protocol used by my Drayton Digistat wireless thermostat, and implemented this protocol on a low cost PIC microcontroller and wireless transmitter. By simulating the "boiler-on" and "boiler-off" codes, it is possible to override the existing wireless thermostat and control the heating directly with your own control system.

I now have a very simple sketch for the Arduino which implements this wireless boiler on/off control.

This leads to possibilities of remotely controlling the heating either from a web browser, telephone link (using DTMF tones) or something as simple as a TV remote control.

7. Individual control of radiators with wireless remote rad-valves etc.

Wireless motorised gearheads are available from Conrad Electronics (search for Radiator thermostats) for popular makes of thermostatic radiator valves (TRVs). These allow complete rooms to be individually temperature controlled, by monitoring the room temperature and setting the local TRV accordingly. It's possible to fool a TRV into shutting off its radiator by gently warming the wax "bulb". It takes a power resistor and about 1W of power to keep a TRV shut. This could be an alternative to a wireless system.

8. Uploading data to web with ethernet shield and datalog/display with Pachube.

Several low cost ethernet shields and gateways are now available which allow data to be sent up to the net for remote hosting, using free services such as Pachube. By using an external microcontroller that hosts the TCP/IP stack and has an integrated ethernet controller, the burden of this is taken from the Arduino. Data can then be communicated to/from the web as simple serial text.

9. Remote control/ access to heating system via web browser / iPhone app etc.

Once you have an ethernet connection to your central heating controller, remote access and monitoring is possible via web browser or custom app running on iPhone or Android etc. Not my immediate field of expertise - but many HomeCampers are working on similar apps.

10. Back-end datalogging, graphing and analysis (Ubuntu, Joggler, Processing etc).

A serial or wireless connection from the central heating controller to a laptop, PC or other graphical platform allows historical consumption to be logged and displayed. The O2 Joggler is a particularly economically priced platform capable of running Linux/Ubuntu. Again, whilst not my area, there are many hacking various platforms and re-purposing them for home automation applications.

Remote Possibilities

The infra-red remote control unit arrived from NuElectronics with the RTC and SD datalogging sensor shield. The photo shows the combined stack of three boards, Arduino, RTC and ethernet shield. The IR sensor for the remote control is plugged into one of the inputs on the sensor board.

This assembly now provides the building blocks needed for a stand-alone, real time sensing system, with local datalogging and ethernet/Web accessability for between £40 and £50 of off the shelf hardware.

In my opinion, this now puts remote sensing well within the capability of the enthusiast or hobbyist, and with free, on line data hosting and graphing services such as Pachube, brings an interesting new dimension to home monitoring and control projects.

So what is needed now is a convenient way of stitching this lot together with opensource code modules, to allow quite sophisticated applications to be rapidly developed. In discussions with Trystan Lea of openenergymonitor, this could be done using the Arduino code libraries.

However, I believe that there is ultimately an opportunity for a PC application, which allows you to quickly chose the functionality you need, and the PC then compiles the relevant code libraries into the final sketch.

For example, the "Configurator" application would allow you to select what hardware you have assembled - from a list of popular vendors, in a mix-and-match manner. Then you select the functionality from a similar list - eg. RTC, datalogger, ethernet client, and define the sensors you have connected. This is then compiled with other operating parameters - eg. MAC address, logging frequency etc to produce a sketch tailored to your particular application.

Whilst most of the above is beyond my programming skills, it would certainly hasten the development of complex applications and make the system more accessible to new users.

Solar Controller

I've been working on a simple solar heating controller based on an Arduino open source hardware microcontroller.

The design was inspired by Tristan Lea's unit on his openenergymonitor blog, and it was a project that I had been meaning to get around to doing on return from China.

Trystan's unit used PT1000 sensors and an analogue multiplexer and op amp circuit to scale the sensor readings. I decided to use 10K NTC thermistors because they are cheap and easy to use and accurate enough for this sort of application.

http://openenergymonitor.org/emon/node/70

It started with a nice blue LCD from Moderndevice, which comes with a LCD117 PIC based controller kit which makes displaying text as simple as serial.print statements from the Arduino.

http://www.moderndevice.com/products/16x2lcd-lcd117kit

It connects via a 3 wire interface, making it easy to have the display some distance away from the Arduino board. There are 3 spare outputs on the PIC for driving LEDS, and one can drive a piezo buzzer. The PIC allows the brightness of the display to be controlled using pwm.

It took about an hour to assemble the kit and get the display to show analogue readings from the Arduino. I also wrote a bit of code to display the time, counting in seconds and displaying leading zeros where required.

The next thing was to interface the analogue input channels to the temperature sensing thermistors. I had some pipe clip thermistors from Rapid Electronics, which will clip directly to 15 or 22mm copper pipe.

Using code on the Arduino forum to linearise the signal from the thermistors, I soon had them displaying in degrees centigrade. The linearisation uses the Hart-Steinhart equation which is simple in C, but previously had been stumping me to try to write it in assembler.

http://www.arduino.cc/playground/ComponentLib/Thermistor2

The Arduino will read up to 6 thermistors on its analogue inputs, but I chose to fit 3 and a variable resistor "pot" which allows me to define a set-point.

I'm not quite ready to fit the controller onto my solar panel system, so I thought I'd use it to monitor the various temperatures of my hot water tank. The Arduino outputs its thermistor readings to the display once per second, and also via the serial/USB interface to the laptop. They are generated as a CSV delimited file which can be read in and stored using the likes of Hyperterminal and then manipulated and graphed using Excel. The graph shows temperature of my hot water tank (red) heat up when hot water from the gas boiler (blue) is pumped through the heat exchanger coil.

I've realised for sometime that the Arduino could be much improved with the addition of a dedicated Real Time Clock and data storage using a SDcard interface. I learnt this week that NuElectronics have recently released a new shield combining RTC and SDcard. It also has 6+2 connectors allowing 1-wire or 2-wire sensor devices to be connected to it. More details here:

Similar products combining SDcard and RTC are also available from Lady Ada and Seeeduino Studios.

This new shield will transform the Arduino into a datalogging hub forming the basis of an integrated energy monitoring system - along the lines of Trystan Lea's openenergymonitor. With an ethernet gateway, the real time and logged data could be made available to the net via such services as Pachube.

Here are a few ideas how it could be used:

1. Solar Water Heating Controller - simple control with circulation pump relay
2. Central Heating / woodburner controller - determines best usage of hot water
3. Electricity Monitor - whole house electricity consumption
4. Gas consumption monitor - pulse counter on optical sensor on gas meter
5. pV / battery charge controller/datalogger
6. Gasifier controller
7. CHP controller - engine start/stop, rpm, voltage monitor etc
8. Battery management system for wind or solar pV.
9. General purpose sensing, datalogging and control tasks
10. Temperature, climate and weather monitoring and datalogging.

What is needed now are some standardised communication protocols to allow Arduino based hardware modules to communicate with one another, and the central hub and thus via the ethernet link to the web.

Eating Out in China

I now come to the third part of my short series of observations about everyday life in modern China.

We have all seen TV documentaries of the bizarre cuisine in China, such as a couple of years ago when Paul Merton had lunch and interviewed a crazy woman in a restaurant that served snake and donkey penis.

Fortunately I have not yet stumbled across such establishments (or women), mainly because of self-preservation mantra “Stick to what you know”.

A Hong Kong friend man told me many years ago “If it moves – the Chinaman will eat it” – this was of course the abridged version, it should actually have been:

“If it slides, slithers, swims, scurries, scuttles, slips, creeps, crawls, climbs, dips, dives, hops, hobbles, jumps, jives, walks, wades, waddles, flys, flaps, flounders, flutters, frolics or f**ks – the Chinaman will eat almost every part of it”.

With this in mind, there is a high probability that you will encounter unfamiliar foodstuffs – so I offer this short guide to eating out in China.

The working title of this episode ought to be "How to retain your health and body weight - whilst all around you are trying to poison you".

Whilst living in a 5 star hotel, there are of course the hotel restaurants, Western, Chinese and Japanese style - as well as a revolving restaurant on the 24th floor, from where you get a panaoramic view of this area of Shenzhen's surrounding suburbs. We're next to Shenzhen airport here - so imagine it a bit like Staines or Houslow but a lot more densley built with high rise appartments. The Western style restaurant is at best disappointing, the others are over priced - so by way of adventure - and to get out of the hotel at night, I risk life and limb, cross the streets to the town centre and seek out local culinary diversions.

There are many outlets offering food in China, these range from market stalls selling snacks in the street, small makeshift eateries – that look that they adopt a fly by night strategy to avoid hygiene inspection, “mom & pop” family run restaurants – which is what folks drift into when they accidently end up with more than one daughter, and finally a multitude of specialist restaurants, offering food from all regions of China.

There are of course a plague of Western franchises, KFC, McDonalds, Pizza Hut, Starbucks – these tend to be common in the cities and the larger towns – the restaurants of last resort. In 30 years the next generation of Chinese will be unrecognisable - already the Hong Kong youth suffer from imported obesity from a diet of western junk food. (There's gotta be a pun there somewhere).

Street Cuisine.

This is literally prepared in the street and consists of simple foodstuffs or snacks, cooked or barbequed on charcoal or gas braziers mounted on modified tricycle stalls. The food often consists of barbequed or deep fried fritters/critters on sticks and sell for 2 or 3 Yuan. In homage to Monty Pythons “Chocolate Box” sketch, “Crunchy Frog” or “Lark Surprise” may well be on offer. A disguise of golden batter makes even the most exotic appear appetising.

Other stalls offer omelettes, pancakes, hard boiled eggs and fried waffles. Some traders offer carved pineapple, lychees, grapes, bananas – fruit that can be eaten “on the go” plus lengths of sugar cane to chew on – and then have to spit out great wads of sugar cane “cud”. Some stalls have a special cane-crusher machine mounted on the back of a trike – and offer freshly squeezed cane juice.

My advice with all street food – is try at your peril. The cooking facilities are at best basic, the vendors have no means to keep hygienic conditions, and any water used may be straight from the local tap – and really should be boiled before consumption. Bear this in mind with any fruit, that may have been handled or washed in the local water.

So how bad can it be – everyone will have had a “dodgy burger” from a catering trailer at an outside event – but here in China, the implications can be a little more severe. Best advice is stay clear of street food – just ‘cause the local factory workers can eat it – is no guarantee that your metabolism is quite ready for it.

“Fly by Night Cafes”

These consist of a mixed assortment of plastic tables and stools arranged outside an open shop, often under a fold out canopy to keep out the sun and rain. They are found predominantly in the industrial zones – directly across from the factories. They offer low cost eating for factory workers – as an alternative to the rather institutionalised works canteen. Meals will be about 10 Yuan (£1) per dish, and are served with a plastic mug of warmish water. If you eat in these outlets – don’t look too closely at the decor nor the serving conditions. Make sure they use new, disposable chop sticks – individually packed in a paper wrapper. These cafes offer budget eating, but at the end of the day – you get what you pay for.

Next up the hierarchy, are the family run restaurants. These usually have about 30 to 50 seats arranged around plain wooden tables. The service is polite and if you attend frequently, they get to know you and what you prefer to eat. A meal consisting of a bowl of soup, a rice or noodle dish and a large (600ml) bottle of Tsing Tao beer can be had for 21 Yuan (£2.10). I usually have fried rice with shredded beef or pork for lunch at such a place close by the factory. Fried rice by its nature is cooked at high temperature and the thin shreds of meat are also well cooked and easy to eat with chop sticks – this is an important consideration if you new to chop sticks. Whilst more elaborate dishes are available, such as pork chop, beef medallion or roast chicken – these are not so easy with chop sticks and involve either a lot of gnashing of teeth or man-handling like barbeque food.

The Chinese have a particular desire for food that offers “mouth feel”. To the unaccustomed Westerner, this means bony, lumpy, gristley or chewy and downright awkward to eat without having to eject bits onto your plate. Whilst this might appear bad mannered in the UK, it is common for anything inedible to be ejected directly onto the table cloth – so no need to be embarrassed – you won’t offend anyone. Table manners, like driving skills, are mostly absent here. Soup is slurped, rice scoffed from bowl to mouth, bones spat out, extra gas belched and teeth customley picked at the table.

A particular note about roast chicken – for the uninitiated. In the UK we generally joint our chicken into easy to manage portions, legs, wings breasts, making it easy to eat, either by fingers at barbeques or with a knife and fork. In China, after roasting a chicken, they put it on a chopping board, and section it laterally across the rib cage with a very sharp cleaver. This leaves a series of strips of flesh, about half an inch wide, each featuring its own bits of cut rib bone – another hazard and pitfall for the chop-stick newbie. This means that if you order chicken, it will be served on an oval plate, in the above fashion – still with the head at the end of the plate.

Specialist Restaurants. These abound in all the big towns. They are normally based on some regional speciality, such as Hunan, Szechuan, Cantonese (Hong Kong Style), plus Vietnamese, Thai and Japanese. I will describe two that I have had some recent experience of.

Hot Pot. This is a style from the north west of China, close to the nomadic sheep and goat herding areas of Mongolia. If the restauranteurs are genuinely from this area, they will be tall, muscular and ruddy faced. The dish consists of a large stainless steel pot of hot, spiced lamb broth – similar to a round washing up bowl, full of a liquid that looks like dirty dish water, which is kept hot by a gas burner set into the centre of the circular table. During the course of what is usually a 2 hour meal, you order various types of wafer thin sliced meats, meat balls, vegetables and mushrooms which you broil for a few minutes in the broth and eat with bowls of rice. As the evening proceeds, the broth thickens with the fats and juices from the cooked mutton. The hot pot is a very sociable meal, and a good opportunity to chat – so best attended with at least 4 people. Remember to take your interpreter – it’s almost impossible to order the right mix of dishes without someone who speaks the lingo. Wash the whole lot down with copious quantities of cold Tsing Tao beer. They do a spicy variant of the above dish – which is definitely not for the faint hearted. I tried it once and it was disappointing – way too hot for general consumption.

Maojia Restaurant.

This is often called “Mao Style” and it is a regional style from the Hunan province, where Mao was born. It is characterised as being hot and spicy, copiously involving the use of red and green chillies. If you are “up for a curry” this might just suit you – as curries are either non-existent or disappointing in this area. Dishes consist of meat or fish, served on a sizzling iron platter of red and green chillies. If you are lucky, the restaurant will have a picture menu – so best is to look for the ones that don’t have so much chilli – this can however be a bit of a “point and prey” lottery – rather like pinning the tail on the donkey. If you are lucky, the dish will be more or less what you expected, but I did once order liver rather than beef, as the picture was a bit unclear. The chefs tend to chuck in a lot more chillies than the picture might suggest – and I had one dish earlier this week, that was over-endowed with green chillies and almost too hot to enjoy.

Ordering from anything other than a picture menu is difficult, if dining alone. Fortunately I often have a Chinese friend with me, who keeps me out of trouble. I have however picked up a few words that usually result in the right dish being delivered.

A typical conversation in the restaurant might be:

Nihau - “hello, how are you”, then raise one digit to indicate that you are a sad lonely, singular western diner.

Nu yo chow fan - this normally is understood as fried rice with shredded beef.

Tsing Tao pee-jew – this will bring you a bottle of the local lager and a very small tumbler glass – this week there was a Tsing Tao promotion, and the nice girl in the Tsing Tao T-shirt put down a shot-glass not noticing that there was a small dead cockroach in the bottom. I pointed out her error and she got me a fresh one.

Fuwu yuan - “Waiter”

My Fan - reminds them you want a bowl of steamed rice

Ma Dan - bill please

She-she - thankyou

Bye bye - good night and thanks for having a giggle at my expense but hopefully not poisoning me. I’ll know within the next four hours.

Here’s some things I learnt during my odyssey:

During the course of your meal, expect lots of shouting from neighbouring tables when it comes to either place the order or discuss the bill. Smoking is still common in restaurants.

Don’t fret if you see a waiter with a fishing net go to the fish tank and bring back a live fish and head for the kitchen. They like their fish very fresh here. One barbaric delicacy is a live fish dunked tail first into hot oil, with its head and the chef's hand wrapped in a wet tea-towel. It is still (barely) alive when served at the table. Makes the "Spooks"/ deep fat fryer scene look quite tame really.

The “mom & pop” restaurant where I have lunch has a back kitchen with blazing gas burners. Occasionally there are minor explosions and loud “whooshes” and flames seen from the kitchen as the oil mist ignites over the gas burner – makes for a more exciting cooking experience.

If it looks like battered onion rings but very chewy, it’s probably sliced rings of pig intestine fried in batter.

Having started a meal in a small restaurant, I once saw a large rat make a bid for freedom, run from the kitchen area, across the restaurant and out of the front door. Rat was probably not on the menu – so I didn’t fret too much.

So now that we have got the polite aspects of eating out in China out of the way – I would like to warn you about some of the after effects and how best to cope with them.

Fortunately restaurants give you a plastic packet of about 8 or 10 folded napkins. These are great for wiping grease off your chin when struggling with chop-sticks – but at the end of the meal, keep the rest of the packet, put them in your pocket and take them with you – you may need them later.
Chinese restaurants seldom have western style toilets, so plan your evening so you are not caught short at the restaurant. Aim to base your daily business about the hotel, as western toilets, loo paper and soap are seldom found outside the hotel.

Last year, three of us staying here, who had a hot pot, suffered in the night and for most of the following morning. We had a bit of a laugh about it – put it down to bad luck, and returned to the same restaurant a week later with no similar effect. The effects are short lived and soon over within 12 hours.

Fuelling the Fires of Industry

The second of a short series of posts about day to day life in Southern China.

The miracle of economic growth that has blessed China in the last decade, has left a population rapidly trying to catch up with the rate of change. Agricultural villages in the Shenzhen, Dong Guan, Guang Zhou "Triangle", have expanded into bustling industrial towns in the matter of just a few years. Farm fields sold off to developers to produce industrial zones of identical factories and tracts of urban housing apartment blocks.

The rate of growth can probably be likened to that of the London boroughs during the 1830s in our own Industrial revolution - just on a much larger scale.

Modern factories compete with simple workshops - often located in the main street. It is common for the various traders to group together - for example, one Sunday morning in Chang An, I passed about 20 shopfronts all of which specialised in stainless steel wire and pipe.

The photo at the top shows a metal fabrication workshop in Chang An. Steel stock is piled up in the street and cut into the necessary profiles with simple jigs and gas cutting torches. Here a worker is cutting circles from heavy gauge steel plate.

Amongst this new urban chaos, live the bemused population, - factory workers, shop keepers, handymen, porters and the recyclers of which I spoke last time. The three cities named above are home to nearly 35 million. Equivalent to half the population of the UK, shoe-horned into an area less than the size of the southern Home Counties.

Keeping this population moving are a series of modern dual carriageway roads and 3 to 4 lane expressways. Competing on these roads are a mix of trucks, buses, vans, cars, motorbikes, auto-rickshaws, electric scooters/mopeds, bicycles and pedestrians - in roughly that pecking order.

To the uninitiated Westerner, the road traffic looks like total chaos, ungoverned by any rules or regulations. However, somehow, the system seems to work in a way that would seem impossible in the UK.

To understand the system, you have to discover a few things the hard way - if you survive the first time you cross a pedestrian crossing - you have cleared the first Darwinian hurdle. So here are the 3 things you need to know - "Three Steps to (avoid) Heaven".

First of all, there is no concept of "right of way". Most drivers will cut across the path of oncoming vehicles, loosely based on the pecking order above, and a quick decision on the size, speed and braking capability of the oncoming vehicle. It seems perfectly normal for a car to turn left across an on coming stream of motorcycles and electric mopeds, expecting them to slow down, stop or change their direction.

Secondly, road markings, such as centre-lines, double centre lines, stop lines and zebra crossings mean little if anything to the average road user. If your lane is blocked - then use the other carriageway, even though it might involve playing "chicken" across the centreline (or double centreline) with the oncoming traffic. If they are "just" bikes and scooters, they will probably part out of the way, if they are bigger than you, just barge in front of the obstruction you just overtook, and carve them up. My driver has scared me on many occasion by first overtaking and then carving up a 40-tonner with a fully laden shipping container on the back!

Thirdly, blowing the horn at every second vehicle appears to be mandatory, whenever other road users come in your way. Chinese cars should be designed with no indicators - totally redundant - but an extra horn or two controlled off the redundant indicator stalk.

Horns are used in advance to warn other slower road users or pedestrians that you have either no intention of stopping (see concrete trucks - below), so they should get out of your way, or as an indication to other slow road users that they are in your way and should change lanes or yield. There is no lane discipline, so you will commonly find a poor soul on a pedal-trike, or auto-rickshaw, holding up a queue of traffic in the outside lane of a 2-lane street. No problem, just undertake on the inside, comandeer the opposite carriageway or even the pavement if it looks easier - just keep moving, by whatever means possible.

The worst offenders are concrete trucks - the revolving type. Time, tide and setting concrete waits for no man - and the drivers of these trucks drive to the max, often with the horn on at all times - especially if there may be bikes or people crossing the road that might get in the way of them.

Pedestrian crossings are widely ignored. If you are a pedestrian on a zebra crossing, you often have to dodge oncoming vehicles or freeze like a bunny in the headlights as buses and trucks pass you on each side. Light controlled pedestrian crossings are almost as bad. Even if the green man is illuminated, there will be someone jumping the lights, sneaking a right turn on red, and generally trying to wipe you out.

One way steets are generally ignored - it is common to have to avoid oncoming traffic driving the wrong way on the slip road to the dual carrigeways. Exiting a carriageway on the "on ramp" is a common dodge if it will save you a few seconds - regardless of what happens when you come into conflict with those trying to get onto the carriageway. Even the buses and 40 tonners do this!

At night, the perils are a bit greater. Electric bikes are virtually silent and few use their lights after dark - a way of extending the range. Car drivers often drive without lights, use of lights and windscreen wipers appears to be arbitrary.

Even on the pavement, the pedestrian will still encounter road users. Cars will drive on the pavement if the road ahead is blocked. Bikes, trikes and e-bikes will sneak up on you on the pavement and then expect you to yield.

Most residents in the industrial towns are young and inexperienced of road traffic. Factory workers from rural towns flock to the urban areas and have little or no traffic awareness. Just by looking at oncoming traffic when they blindly stroll across the road would be a good starting point. Many are oblivious to oncoming traffic until they hear the blast of the horn. As darkness falls at 7:30 in this lattitude - workers exiting from an evening shift, at the end of a 13 hour day are generally oblivious to the container trucks that thunder through the industrial zones.

China still has a relatively low traffic density, which is probably the only reason that it can move in this manner. If car and vehicle ownership is to rise, then it must be followed with a roadsense awareness campaign - starting in primary school. Only then will they manage to increase their vehicle numbers and keep it flowing - and slowly move to a system like the West, based on discipline, rules and awareness of other road users. Currently you have to drive here in a manner that assumes that there will be a stationary object around the next bend - or at least expect a vehicle of any size or type to inexplicedly cross your path without notice.

Seatbelts are seldom fitted to cars. Taxis fold away the buckles under the back seats so that they cannot be fastened.

Youngsters are rapidly becoming more mobile with the introduction of affordable electric mopeds. It is common to see a lad riding, with his girlfriend riding side saddle on the back. "Three-up" on a scooter is not uncommon, and I once saw a family of 4 conveyed on one - oblivious to the danger that their children might be in, should they be struck by another vehicle. The other day, I saw a young mother riding a moped, with a toddler, squeezed between her knees, riding on the "footplate" at the bottom of the battery housing. He was unable to hold on, but just gripped between his mothers legs.

Every day one witnesses the bizarre, the foolhardy and the downright dangerous, but somehow the system works, and there does not appear to be a huge amount of carnage on the roads, ambulances or wrecked vehicles littering the highway.

To those of us that have learned our driving skills in the West, the traffic conditions here are alien at best. Who knows what our very own Health and Safety Inspectorate would make of it - perhaps they would become deeply traumatised, realising that they were powerless to change the ways of the population here. Perhaps we could wholesale export the HSE and all their minions to China?

Next time I will cover food, eating out, and coping with other unpredictabilities brought on when living in this quaintly crazy place!

Steet Life in Modern China

Some of you will know that I have spent most of the last month in Southern China, working in an electronics factory.

After 3 weeks of "putting up" with the basic living conditions, the squalor, squat toilets, the mad traffic and the lack of written or spoken English, I guess cabin fever begins to set in.

It came to a head last night when my boss decided that it would be good if I spent another week here, but sadly I only have a 30 day visa - so I'm back on a plane next Wednesday.

Whilst cooped up in the hotel room in the evenings - it is dark by 7:15pm, and the streets are not safe more than a few 100 metres from the hotel, you spend the time reading internet forums and blogs, listening to the BBC World Service and Radio 4 - and having a couple of beers.

Tsing Tao Beer, sells for about 30 - 45p a 600ml bottle in the convenience store around the block, but in the hotel bar, a 330ml bottle is £3.50 - talk about exploiting the guests! So I tend to support the local shopkeepers and buy my beer outside of the mad oasis, I find myself bunkered in.

The empty bottles are recyclable, and 4 bottles will fetch about 1 Yuan or 10p. Tonight I dropped off 8 empties, on the way around to the store.

At night, the streets become alive with those that perform the recycling function. Men and women on trikes and motorised 3 wheelers, tidy up the streets of all the cardboard, glass, packaging, food waste that is produced by the businesses in a busy town during the day. If it were not for these nocturnal workers the town would drown in it's own filth. Nothing goes to waste - this economy cannot afford to waste anything of value - no matter how small that value might be.

Particularly noticeable is the 3-wheelers with a couple of blue barrels on the back. These belong to the grease collectors, and they perform a nightly function of clearing the hotel and restaurant drains of the coagulated fat that collects in the grease traps. Tonight I passed a couple of them, clearing the traps of this hotel, using a sieve on the end of a bamboo pole. The stinking grease is collected in the plastic barrels and then taken somewhere where it is rendered down, filtered and probably goes towards making fuel for the basic tractors that they run around here.

As I left the £60 a night, 5 star hotel, I spared a thought for the old man collecting cardboard onto his tricycle at the back of the hotel. I gave him the 8 empty beer bottles, which he gratefully accepted - with not a little incredulity. The 2 yuan that these fetch, will probably mean that he eats a little better tonight.

The minimum wage for registered workers in this area is 1000 Yuan (£100) a month. For those that have migrated from the rural areas and do not have the correct urban "hukou" registration papers - their chances of a minimum wage are totally non-existent - they are not recognised by the state and have no entitlements - a virtual slave class in what was supposed to be an equal Communist society. Hence their seemingly scavenging life, not only provides an essential service for the district, but provides for them a very meagre source of income. China provides no welfare safety net for the elderly, infirm or out of work. The Hukou system has effectively forced a two tier society of the waged and the unwaged. The rural migrants do not appear on any unemployment statistics and are thus effectively hidden from the official figures - however, they are very much in existence, and very much present for those who only care to look.

So when you buy your laptops, iPhones, iPods and solar panels from China - don't worry about the factory workers. They are the lucky ones working in relatively well paid jobs. Of greater concern is their parents generation, outcast in the 1960s by Mao's radical reforms, and in 40 years are still out of kilter with "modern" China, and will remain so until they work themselves towards an early grave.

A View of Modern China

For the last 4 weeks, I have been working out in southern China, helping out with production of a consumer telecom product.

I was staying in the industrial town of Fu Yong, which is very close to Shenzhen Airport.

During my stay there, I had the opportunity to write a few entries based on my daily observations.

These will now be reproduced in this blog over the next few days.

I have been traveling to southern China since 2000, and have seen the rapid rate of change over the last 10 years. My job takes me onto the factory floor of the modern electronic manufacturers and I spend time working with Chinese workers on the line.

As a design engineer, the move to Globalisation has meant that the products I work on invariably get manufactured in China. So in ten years, I have nurtured five products through the initial stages of manufacturing, solving design problems, testing for faults and generally ensuring that production goes as smoothly as possible.

Language is often a problem, but I have been lucky that I have generally been accompanied by an English speaking local engineer.

Life in 21st Century China is basic, but fascinating - as I hope the next few posts will illustrate.

Nano Technology

March has been a frustrating month - I feel like I have just emerged from an extended illness - and am now feeling a lot better.

In all truth, this is the case. For 2 weeks, from 5th March - I had a really chesty cold which refused to shift. Meanwhile, my old Toshiba laptop was going through its own strains of virus infection - which have proven almost terminal.

Whilst searching for some antivirus software, I accidently landed on a bogus website that automatically installed the "av.exe" virus. Within seconds a fake "Windows XP Security" window appeared and claimed that I had 29 viral risks. It then encouraged you to click on a register for upgrade window - which either wanted to harvest your credit card details, passwords or get you to enter the Product Code - supplied on every legitimate copy of XP.

If you didn't choose this option, it sent very irritating popups every 30 seconds telling you that your machine was at risk. Enough was enough - this malware had to go. So I googled "av.exe virus" and got on a forum discussing how to remove it. However, the av virus was a robust little bugger, and if you just delete the av.exe file, it trashes your registry, so you cannot run any application that uses the .exe file extension. This I found out to my cost. After much gnashing of teeth and tinkering in the registry, I finally got shot of this plague - took me a whole day to get things back to normal.

However, the old Toshiba was running as slow as a 1 legged arthritic dog - so I bit the bullet and treated my self to a new Dell Inspirion - which I am typing on now. It turned up an hour ago, having been sent direct from Dell's manufacturing plant in China - just last Friday. 5 days shipping from China - direct to your door. That is one of the signs that we live truly in a global village.

So I now have a machine that I can host my electronic CAD software on - and get back to doing some real pcb design. In the meanwhile, I have a couple of projects that seem to be following converging paths, and I am looking for an efficient means to use one to solve the problems of the other.

I have been writing an application in C code - and trying to learn C, on the job. About 10 years ago, I borrowed a book from a software friend "Learn C in 21 Days". Well that was about 3650 days ago, and I'm still at the steep point on the learning curve.

From my previous posts, you may know that I have become a fan of the Arduino, and this has been the catalyst, and catapault for me into the exciting world of embedded C programming. For about 10 years I had plodded along with PIC assembley language, preferring to build on code that I had written years before whilst working on telecom products. I never could find the time or justification to switch to C, especially if the job just needed a few lines of assembley to make it run. However, I was finding that I was rapidly running out of steam and my ideas and projects were limited by the fact that writing code for them was just too damm hard. So when the Arduino came along, complete with an online army of code developers who shared their applications and techniques in a big open source "code-fest", I found it a lot easier to rapidly make inroads into C, and develop applications much faster. Whilst I had toyed with the CCS C compiler on the PIC a few years ago, I never really got past the "Hello World" stage.

So, onwards and upwards into the wonderful world of the Arduino, which brings me back to the title of this post. Armed with my new shiny laptop, it was time to buy some replacement Arduinos, as I was down to my last one, and I wanted to upgrade to the Mega328 mcu. So on browsing the Nuelectronics site, I saw that they had the Freeduino Nano for sale for a mere £16.50 complete with the '328 processor. So I settled on two, plus a '328 Decimeillia as a hot spare for the one that I'm developing code on at the moment.

The Nano makes a lot of sense, with its smaller footprint, upgraded processor and a connector pattern that is not only more logical, but not blighted by the stupid connector position error made in CAD some years ago that makes it down right awkward to prototype on Veroboard or breadboard. The Nano has a very compact footprint that will fit into a 28 pin 0.6" DIL socket. It has the added advantage of bringing out another couple of analogue inputs, and uses the much smaller micro USB connector. If only they had had the foresight to put a microSD socket on the back of the board, then it would be a great little engine. Perhaps I'll just have to do my own.

So the Nano is going to play quite a part in future projects. I want to port across a lot of my telecom signal processing routines that I wrote for the 16F PIC. These allow caller ID recognition in firmware and DTMF encoding and decodng, plus a completely soft V23 FSK modem allowing mcus to communicate across phone lines in SMS with very low overhead. Perhaps a bit outmoded in this broadband world - but there are lots of trivial applications where you are miles away from an ethernet connection, and have a few short messages to send.

So one of the first designs I'm working on is an application extender board for the Nano. It's a single eurocard that provides analogue inputs, for temperature or voltage sensing, buffered digital outputs for driving relays or stepper motors, an LCD or keypad interface (Nokia 3310 LCD shield from Nuelectronics) plus some SD memory for datalogging. The applications are for renewable energy monitoring and a wood gas generatore spark ignition and engine control product that I have been mulling over. Inspired by Martin Nile's excellent site:

http://sites.google.com/site/martinnile/

Well Windows Explorer doesn't seem to allow cut and pasting of text - how lame is that? Time to load firefox and dump this Windows crap.

To be continued - under a new regime. Mozilla Firefox. And yes I do want it as my default browser...

At this point Ken downloaded Firefox 3.6.2 and continued life almost normally....

Ok - so windows Internet Explorer really does not allow Ctrl C and Ctrl V. Thank god for sensible software!

So back on the subject of Nanos - here's an even smaller one - just a real shame that they have chosen a different pinout

http://www.gizmodo.com.au/2010/03/the-incredibly-arduino-nano-3-0/

A Change of Tack

My week out in California has got me fired up again on wood gas. Converting the Lister engine to run directly on wood gas and see it perform so well has given me the assurance that wood gas can be made to work for small scale heat and power production.

In the last 5 years I have slowly established an experimental CHP system based on the Lister 6hp diesel engine. Until now, this engine has run on waste vegetable oil, but with WVO getting more difficult to obtain, I realised that a substitute was necessary. The CHP system is located in my garden workshop, known as the "Energy Shed" and the heat and power is brought back to the house via underground pipes and cables.

Following the success in California, it's now my intention to set up a complete wood fired CHP system to heat and power my house. Woodchips are generated as a waste product from tree surgery operations and so there is a glut of this material produced with no real market. Wood chips can be gasified to make a flammable gas to substitute for the WVO fuel for the Lister engine on my generator set. This will produce more than sufficient power to run the house, and the waste heat will be used to provide heat for the house.

A quick calculation suggest that 1 tonne of woodchips will be needed each month of the heating season. This is about 4 cubic metres of chips, which can be stored in a bunker at the front of the house. A converted wheel barrow will be used to transport up to 300 litres at a time, down the side path to a smaller bunker near the workshop holding enough for about 3 days operation. This is defined by the limited access to the rear of the house - everything has to pass through a 3 foot gate and down a narrow path.

A 200 litre drum full of chips will provide sufficient energy to run the Lister engine for about 10 hours. Spare electricity can be stored in the battery bank to run my inverters, or converted to stored heat in night storage heaters. Spare heat will be stored in a 700 litre thermal store, located in the workshop. This will hold about 60kW of heat, which is sufficient to warm the house overnight, and can be topped up from spare heat from the wood-burning stove.

The Lister will be run from about 8am till 6pm, and with adequate silencing and in an acoustic box, should not cause a distraction. It's a Startomatic generator, which can be remotely started. By retaining the diesel injector, it can be started on WVO, switching over to woodgas when the gasifier is fully operational and producing clean gas.

Waste heat from the engine will be used to dry the woodchips, and pre-cook them using a process called torrefication. This pre-chars the chips, driving off water vapour and volatiles, which improves the gasification process. The intention is that the Lister and the gasifier will work in close harmony, where waste heat is exploited in order to maximise the system efficiency.

The 200 litres of chips should produce 25kWh of electricity and 60kWh of hot water. As this household uses about 7.5kWh of electricity per day, the surplus can be used for heating the workroom and workshop.

Knock on Wood

The observant amongst you will notice that most of my posts are named after song titles. This one is no exception. I have just returned from a week long odyssey to All Power Labs in Berkeley in Northern California to learn all about running engines on wood.

All Power Labs is based at "The Shipyard", a kind of creative artists community workspace, based in a couple of industrial units at the south end of Berkeley. They have a well equipped metal machining workshop with big machine tools and a metal fabrication shop. The artists share the facilities and develop great mechanical art projects such as the "Neverwas Haul" (pictured above) which attend festivals such as "Burning Man". Anyway the Shipyard is a very cool place - and I was lucky enough to hang out there for a week, and sofa surf.

Wood can be converted to a flammable gas, by a process known as wood gasification. The woodgas is then used to fuel a converted internal combustion engine. The technology to do this has been around for over 100 years and it was extensively used for running vehicles during WW2 - as documented in the recent book "Wartime Woodburners".

The aim of my trip was to learn how to make the technology work - so I could then set up a similar system in my Energy Shed and derive most of my household heat and electricity from waste woodchips.

So I flew out to San Francisco and crossed the bay to Berkeley - home of All Power Labs (APL) and the GEK gasifier. GEK is shorthand for Gasifier Experimenter's Kit.

APL is the brainchild of Jim Mason, a self taught gasification guru. When the city of Berkeley authorities tried to evict the artists from the Shipyard, they cut the power supply. Jim and his colleagues took the Shipyard offgrid with solar and diesel power and so they could remain operational.

Looking for an alternative to expensive diesel powered generation, Jim and his team re-discovered old studies on wood gasification and so the GEK was developed.

Over the weekend of 19th to 21st February I attended the Gasification Workshop, with 60 other delegates from all over the world. The workshop was hands on experience in working with the GEK gasifier, and other system components.

The fuel for wood gasification is just chipped wood. This drum load was made in a few minutes by running some old pallet planks through a wood-chipper. This sort of material can be obtained from tree surgeons who make so much they can't get rid of it quick enough.

During the course of the weekend we converted a Lister type diesel engine to spark ignition so that it could be run directly on woodgas. The conversion consisted of fitting a long reach spark plug in place of the diesel injector and devising a spark ignition circuit. A new pair of copper head gaskets were made using the CNC plasma cutter, and these were used to lower the compression ratio down to about 13:1.

The ignition circuit was made from an Arduino and a car ignition coil. A Hall effect sensor was used to detect a magnet on the flywheel, placed a few degrees before top dead centre. The Arduino was used to create the correct timing delay and fire off a darlington power transistor with a multi-burst spark.

A friend in Michigan had made a special wood-gas carburettor, which allows the air and the wood-gas to be mixed in the correct ratio. This fitted right on to the air-intake of the Lister engine.

By the Sunday evening we had the Lister running - in fact amazingly it ran first time without major adjustment.

There's a couple of Youtubes showing the conversion. In the first one, I explain to a small group of people what we are going to do and the second one, shows the engine running.

http://www.youtube.com/watch?v=lXPn5Nov9Fg

http://www.youtube.com/watch?v=kXX2GBHoeuo&feature=related

Keep the home fires burning

Freshly emancipated from my job in the city, I have reverted into suburban Victorian mode.

The 3 hours not spent battling with commuter trains are now either spent asleep or doing something useful.

This year we have had the addition of a wood burning stove and backbolier in our living room. This helps keep the core of the house cosy and offsets the amount of gas that we use. However, it must be stated that keeping a woodstove stocked with wood can become a distraction to other activities, more a labour of love.

Whilst man has been using wood to keep warm for millennia, there is a certain amount of skill needed to use it efficiently. Open fires are notoriously inefficient, and even some stoves have much to be desired. In the 21st Century, new wood based fuels are becoming available, and some of the mechanical handling associated with wood fuels can be automated. For the moment, I'm happy and contented to lie on the heath rug and gaze into the embers. Here's a few notes on how I keep this one burning.

Whilst you can just go out an buy a load of logs from numerous local log merchants, the quality is often dubious and you will need somewhere dry to keep them whilst they continue to dry out. Logs are often supplied quite chunky - meaning that further splitting is needed to make them more manageable for the woodstove -- despite its 18" log-length.

Another source of wood is from waste constructional timber. There are many loft conversions going on in this area, and I happened upon a load of roof timbers which were being skipped in the next road - so I offered to liberate them for nothing. These are generally older than 40 years - and so are not contaminated with pressure treatment or wood preservative.

Having cut the longer lengths into 6' pieces, so that they would fit in the back of the van, I hauled a van load back around the corner. These timbers are a nominal 5"x2" but when they are sawn the size is actually about 47 x122mm. They are probably Douglas Fir, and are very dry - so split easily with a hand axe. They are however full of roofing nails and felt tacks - so have to be handled a little carefully with leather faced riggers gloves.

After getting them home, they need to be chop-sawn into a suitable size for the stove. My chop saw has an end stop at 250mm - so this determined the average sawn length. Each 6' timber was sawn into roughly 7 pieces, carefully checking the path of the blade for nails and tacks before committing to the cut.

Once cut, the 10" lengths are split with a hand axe into two, generally unequal parts. These "halves" will burn rapidly and release their heat quickly. For a slower burn, whole pieces are used.

Eight of these 6 foot timbers will provide enough wood for two 12 hour burns. If we are both home, and the weather is cold, we light the stove in the early afternoon and keep it fired until past midnight.

The process of cutting up and splitting the roof timbers takes on average 30 minutes including the time to get out the chop saw, carry the timbers to the cutting area and tidy up afterwards.

The box on the left contains 30 of the 10" pieces and weighs 22kg. This gives the wood an average density of 511g/litre, and I have seen these pieces vary in mass from 500 to 800g.

The calorific value of woodfuel is approximately 4kWh/kg so the box represents about 88kWh of energy. Unfortunately, a basic cast iron woodstove is not a particularly efficient converter of wood into heat - so roughly half of this energy will reach the occupants in the room, the rest will be lost up the chimney. This is however about twice as good as an open fire.

Wood can vary in moisture content, depending on how it has been stored, and different species have different calorific values and burn rates. Better stoves do exist, but what is needed is a change in the technology in order to get the most out of wood. This is where wood gasification comes in.

Wood gasification is the conversion of woody biomass into a mixture of flammable gases, which can be burnt at optimum efficiency in a modified stove or burner. Woodgas primarily consists of carbon monoxide CO and hydrogen H2, with small amounts of CO2, methane and half of the mixture consists of the inert nitrogen from the atmosphere. Woodgas varies in calorific value from between one eighth to one sixth that of natural gas. Wood gas can be used as an engine fuel for riunning vehicles, generators and other machinery. In principle, it should be possible to run a whole household heated and powered from woodgas. Well that's the plan.

Next week I travel to Berkeley, California to learn all about wood gasification and how to build wood gasifiers. There is a project planned to convert a Lister diesel engine to run on wood gas using a spark ignition conversion - so that's what I'm hoping to do, learn how it's done and bring the technology home.