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But electrical energy can also be converted to chemical energy. In an alternative world (perhaps not far-off) with relatively plentiful electricity and little oil, we might use electricity to make liquid fuels;

So I conclude that switching to electric cars is already a good idea, even before we green our electricity supply.

Second, to supplement solar-thermal heating, we electrify most heating of air and water in buildings using heat pumps, which are four times more efficient than ordinary electrical heaters. This electrification of heating further increases the amount of green electricity required. Third, we get all the green electricity from a mix of four sources: from our own renewables; perhaps from “clean coal;” perhaps from nuclear; and finally, and with great politeness, from other countries’ renewables. Among other countries’ renewables, solar power in deserts is the most plentiful option. As long as we can build peaceful international collabor- ations, solar power in other people’s deserts certainly has the technical potential to provide us, them, and everyone with 125 kWh per day per person.

A more modest luxury is an electric blanket. An electric blanket for a double bed uses 140 W; switching it on for one hour uses 0.14 kWh.

patio heaters

Electrify transport. There's not much to beat trains+bicycles, and any government looking for a Keynesian stimulus should find lots of infrastructure opportunities here. David MacKay comes down softly on the car---which shows great realism---and finds that electrification is the only real solution there. He debunks hydrogen as a good energy carrier. Flying is a really tough case---there is not much that can be done to reduce its energy intensity. (I was sitting in an easyjet plane the other day that tried to convince me of its greenery by saying: "Flying contributes less CO2 than driving to the atmosphere" ...). Batteries are the way to go---though just wait for the peak lithium scares. David has an interesting aside on nuclear ships. If we could make the (political) world safe for small-scale nuclear power, maybe there's more than ships that could benefit.

Many gadgets consume a surprising amount of power on standby. David cut his electricity consumption by half by making sure his "vampire appliances" were kept off. There are real savings available here. David and friends set up "ReadYourMeter.org" to try to encourage others to make this sort of saving. According to the International Energy Agency, standby power consumes a surprising8% of residential electricity.

We use about as much to heat and cool ourselves (in Britain) as we use to move around in our cars, while lighting uses onlu a graction of that energy - especially using low energy fluorescent bulbs or the new generation of LED lights. Hydro-electric power in Britain, however, even with generosity from the wet Highlands, will only deliver about one third of the small amount of energy we use to light ourselves. How unfortunate that such accidental power-concentrators as mountains and streams are not more plentiful, and not just, maybe, for the energy benefits.

Feb 7 2009. Join the Group Read. Chapters 5 and 6. Flight and Solar Will solar energy technologies allow us to sustainably take those long-haul flights to get our winter dose of sunshine? On the way, we discover that flying intecontinentally once per year has an energy cost slightly bigger than leaving a 1 kW electric fire on, non-stop, 24 hours a day, all year, despite the fact that modern planes are twice as fuel-efficient as a single-occupancy car. It may be no surprise, therefore, that Airline businessman Michael O’Leary, CEO of Ryanair, has developed a Swiftian the solution to the problem: " The best thing we can do with environmentalists is shoot them."

A final impediment to rational discussion of combined heat and power is a myth that has grown up recently, that decentralizing a technology somehow makes it greener. So whereas big centralized fossil fuel power stations are “bad,” flocks of local micro-power stations are imbued with goodness. But if decentralization is actually a good idea then “small is beautiful” should be evident in the numbers. Decentralization should be able to stand on its own two feet. And what the numbers actually show is that centralized electricity generation has many benefits in both economic and energy terms. Only in large buildings is there any benefit to local generation, and usually that benefit is only about 10% or 20%.

Chapter 18 was depressing --- the diffuse nature of renewables in the crowded UK basically means that a realistic view of their usage makes it clear we won't make it on local wind, tide, sun, geothermal, wood etc. Assume: a) we can't change energy per capita too much; b) we can't change the capita (ie no creepy population control) and we still want sustainability ... The basic solution is:  1. electrify transport 2.  electrify space heating 3. produce electricity with whatever local renewables we can, augmented by clean coal, nuclear and imported solar from desert regions. Sounds simple, no?

David adopts an avowedly arbitrary definition of a sustainable burn rate: can a burn-rate be sustained for 1000 years? If yes, it is sustainable. That definition allow shim to relate the UK's coal reserves with a daily per person sustainable consumption rate --- there would be less than 1 kWh of electricity per person available from clean coal. But we consume 180 kWh/day/person, so clean coal is a stop gap --- it will not see our way of life go on for that long. This relies pretty crucially on the definition of sustainability, which I think is wrong for the purpose. David adopts what one might call the Ise Shrine notion of sustainability. The Ise Shrine was first built in 4BC and has been rebuilt, identically, ever since then every 20 years. It was last rebuilt in 1993. This is "sustainability" as in keeping on and on doing the same thing. David is ISe-esque in choosing our ability to do the same thing - burn British coal - for a very long time to come.

The nuclear decommissioning authority has an annual budget of £2 billion. In fact, this clean-up budget seems to rise and rise. The latest figure for the total cost of decommissioning is £73 billion. news.bbc.co.uk/1/hi/uk/7215688.stm