In 2007 we replaced the old Gas Boiler that was on the wall in the kitchen. It was fourteen years old as it was the original fitted to the new build in 1993. It was replaced by a new A-Rate Condensing one - a Worcester-Bosch Greenstar. The old boiler looked very outdated in comparison. The Greenstar looked more like a Computer on the inside than a boiler. These condensing boilers require a drain for the water than condenses out of the exhaust. So a pipe is connected an outlet. In our case directly to a downpipe from the roof. The intention appears to be that this will protect it from frost - although make it difficult to maintain the downpipe.

During the installation you will have to live without heating for a few days so schedule it for the warmer months.

If you invest in a new Boiler you should update all of your "peripherals" - your timer/controller and radiator regulators. The timer/controller allows you to program Hot Water &/or Heating for different times of the day and night. Old controllers mostly only have one setting for every day of the week. This would be the same for Hot Water and Heating. New models allow different timings for Hot Water and Heating so they work independently. It also has different programs for week days and weekends. So we can all have a lay-in bed and still have warmth and Hot Water when we need it. It even allows three periods of Hot Water or Heating through the day. The old one only allowed two such periods so things got cold at midday. It stops you having to forever switch the Heating or Hot Water on or off. It should look after itself whilst avoid creating Hot Water and Heating when there is no one around to use it.

We also took this opportunity to put in  "TRV's" - 'thermostatic radiator valves'. They are recommended for most radiators in the house so that we can control the temperature more efficiently. So if a room gets too hot the valve will shut off the radiator.

Note: most people are confused by their heating control and just leave the Hot Water and Heating on all the time. This is extremely wasteful. You need neither in the middle of the night and when the house is empty during the working week-day. You will save a bucket load of  money by not heating an empty house. Save that gas for the time when you care, ie, when you are in your home and awake!

A typical 3 bedroom House in the UK is alleged to use 3,000kWh per year. During 2007 Post-Carbon Home One (a three bedroom house) only consumed 2585kWh. So we were doing relatively well. However, our Photovoltaic Solar Panels pump out about 1,100 KwH every year plus we export enough to suggest that the solar panels make up over half of our total yearly requirement. Indeed, in 2003/2004 this house consumed 4421 units. We don't know why this is so much higher than the average but we have conjured up a 44% drop in Electricity usage. How did we do this? Like so....

Tucked away undisturbed in a discrete corner we had an "EPS 188" plugged into a wall socket. It was an experiment. It came from www.windtrap.co.uk (£39.95 GBP). It is meant to optimise the house voltage to save 10 to 20% of electricity by 'filtration and correction techniques'. Factories with many electric motors and transformers do need Voltage correction devices. So it MIGHT be something like that. It is complicated to explain and is wrapped up in the physics of Alternating Currents (AC) and electromagnetism. Or it could just be an empty box with a red light. However we do know that it does have a peculiar effect upon the Electrisave readout. Generally it reads higher than actual usage but then lower when ever an elecric motor is used. Mostly it is left plugged in out of paranoia that it might work.

Also from Windtrap we have the 'SavaPlug' that fits most models of Fridges. This replaces the ordinary three pin plug. You have to wire it in so you will need some basic knowledge on how to use a screwdriver and a pair of scissors! It works by damping the electrical spike that results from the compressor coming on. It stops the motor from running at full power unnecessarily. It is claimed to save you 20% of your electricity or £12 GBP per year. It cannot be used on fridges that have digital displays or motorised drink/ice dispensers. We left this in Post-Carbon Home One when we moved. Many Engineers doubted it usefulness.

Next up we have all those energy-saving light bulbs. We had around 28 of them including two in the attic and one in the garage. We were quite obsessed by the CFL and we would have one in the fridge and one in the oven if we could! It has been a struggle to find the ones that fitted all our sockets. We resorted to contacting manufacturers and paying quite a lot of money to get them specially ordered for us. If you have a remotely strange light fitting they become difficult to find. This was true back in 2005/2007 but is becoming less of a problem these days (2009) as each niche is filled. However you may still have to order online.

We used to have a big problem with Standby on our electrical devices. None of these devices had an off switch and the wall switch was buried behind furniture. So we started to use a device called "Bye Bye Standby". This is just a remote-control switch that you use to switch things off at the plug. In comes in packs of three or four. We managed to get one of the very first four-packs direct from the manufacturer. Now we have seven in total. You can make them work on different channels so they can switch of different devices. We had a "kill" switch for the entire house which we clicked when we went out. We can kill the power to three Televisions, two stereos, one computer, two DVD Players, one Cable TV Box, one remote extender, one Washing Machine, one microwave and numerous small peripheral devices.

However there are doubts. Firstly the remote controls use batteries that needed replacing within weeks of us taking delivery. Secondly the socket you put between device and wall socket itself draws a standby current. Then there is all the embedded carbon in getting these over-packaged Bye Bye Standby kits over from China where they are made. Are they really worth it? We measured their standby current but it was undetectable. So we gave them a thumbs up. After the initial battery problem they have proved very reliable.

Finally we have the Electrisave. We also bought this from Windtrap for £69.50 GBP. Expensive and it doesn't actually save you a thing! It just measures your house power usage like a meter does. However it has a clever display that can show our usage in a big LCD format. It can show the cost or the Carbon output as well as the kWh usage. It also shows the humidity and temperature. Ours sat on top of the TV and is a good way of telling when the Washing Machine or cooker is on. However if you have the presence-of-mind to buy this thing then you are probably very conscious of these things anyway.

The other problem is that it uses a lot of batteries. It sucks the juice out of rechargeables so quickly that you have to keep replacing them. Is this using more power than it saves? You also may have problems installing it. Although the transmitter just clamps around a cable in the Meter Box outside it isn't always clear as to which cable it is. This may deter many users.

In Feb 2005 we had one of our vehicles convertd to LPG. This was on a BMW Z4, which, on the face of it, was hardly a good starting point. At the time we only needed a small two seater that was efficient on the motorway. The BMW was a manual with six forward gears as standard. It was small but had a large boot for the Gas Tank. It had a standard BMW engine so it would be easy to convert. The conversion cost over £2000GBP. The tank gave 250 miles at a cost of only about £18GBP for fuel. This is less than £0.08p/mile whereas running on petrol would have cost £0.14p/mile. So it was money well spent and does eventually pay for itself making it an investment. (Figures for 2007).

The engine has to heat up for about half a mile before the LPG kicks in automatically. You retain your original Petrol tank on a retrofit which acts as reserve. The LPG tank fits in the boot (picture right) but bigger cars can have them fitted underneath the car or in the spare wheel well. The dashboard has a small indicator showing how full the tank is. This also has an over-ride switch allowing you to switch between petrol and gas manually (picture bottom). Most Insurers will insure a dual-fuel car at little or no extra cost.

(Above) LPG Tank tucked in the boot.

However, is it Post-Carbon? Yes and no. We did a lot of research over the years and we now know more than we did when we made that decision. Undoubtedly a car with a much smaller engine would have been better. Lower CO2 emission would have been possible with Diesel but that would have been more expensive and Diesel versions of that car do not exist. Hence this does restrict your choice. LPG also has advantages over Diesel - it produces 20 times less NOx and 120 times less soot. However, when it comes to determining precisely how much CO2 is saved there is not much help at hand. In the UK you can obtain your CO2 grammes per km from New Car Window stickers (it is the law) or from www.vcacarfueldata.org.uk. From VCA Car Fuel Data we knew that the petrol version of the BMW z4 had Carbon Dioxide emissions of 207g/km.

(Above) Engine modifications.

Using this data it looks like LPG saves between 9% (Vauxhall) and 21% (Volvo) based on new cars. However, no data is available for after-sales installation. Supporters of LPG all say it saves 20% but we found that this is a statistical error. In the 2003 "European Emissions Testing Programme" it quotes a 20% INCREASE in CO2 emissions from LPG to Petrol. This equates to a 16% reduction if calculated the other way! Based on this Data we use a figure of 15% reduction. It seems reasonable based upon the performance of similar BMW diesels. Hence we work on a basis of 175g/km putting the Z4 in the top 35% of all UK cars on the market. This is instead of the bottom 40%. It leaps 922 places up the league chart of 3277 cars. This is all good but it could be BETTER.

In April 2009 we sold the Z4 and bought a Toyota Aygo. It was also converted to LPG.

(Above) New button on the dash.