But now I'm left with the small challenge of how to cut my 10% next year! I already took the Energy Saving Trust's challenge to cut 20% and actually managed to reduce my domestic energy usage by a third in 2008 vs 2006. After the cold winter we had this year, our gas consumption actually rose above 2007 (boo, hiss).
I've done all the loft insulation, the windows are good, the wall cavities are insulated, we have no drafts and the house even has a heat-recovery ventilation system so we can breathe fresh air all year round without keeping any windows open. Our lightbulbs are energy-saving, nothing is left on standby, the oldest, most wasteful appliances have been replaced with efficient new models and our solar panel gives us free hot water in summer (though there haven't been many recent days with enough sun to leave the gas boiler off entirely). While I am vegetarian, I don't yet grow my own food or buy strictly local produce: they don't make a lot of meat substitutes in this neck of the woods.
Away from home, we haven't flown on holiday since 2006 and we had cut down to one car since 2007 - although that's now gone by the wayside as we replaced the big family car with a new, frugal Golf and an old Honda diesel estate for holidays and other occasions when the Golf just isn't big enough for 4 adults with luggage and an Irish Setter.
So will my next 10% emissions reduction have to come from our suppliers? Until now, I have resisted switching to green electricity suppliers for three reasons. Firstly, they can't supply renewable gas because its not yet available - although the National Grid themselves have proposed biomethane as a future source for most of our domestic gas requirement. Second, my purchase of green electrons just makes everyone else's a bit more brown without creating additional renewable generating capacity. And lastly, it costs a good deal more than online duel fuel deals from the big 6 utilities. At least Good Energy will now give me a discount for my solar thermal installation but the rebate is comparatively small and unmetered - i.e. it is independent from the amount of renewable energy the system actually provides.
What might make the difference is the Government's proposed Feed-In tariffs, obliging my utility company to buy power that I can generate from micro-renewables. This should kick in next year and I have just the right roof-space for a few square metres of solar PV panels. We use about 5500 kWh of electricity a year at the moment so I would need to generate 550 kWh to meet my 10:10 pledge. That's an average of 1.5 kWh per day, achievable with PV modules producing just 500Wp. The inverters and other feed-in kit are quite costly, though, so I would probably need a greater area of PV modules than this to make financial sense of the overall project.
In the meantime, I do have two outstanding opportunities to cut down on electricity usage. I have known for months that a low-power netbook would minimise the hours that I have this old, 300-watt PC powered up. Today, I have finally ordered LED striplights to replace 4 metres of fluorescent tubes under the kitchen cabinets. For £150 including the transformer, from Ecolightstore, these could save 300 watts for several hours a day, cutting 200 - 400 kWh a year from our electricity usage. I await the family's response to LED lighting with interest.
Perhaps these two investments alone will be enough to cut my 10% next year ...