The electric blanket is back (picture version)

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Open publication - Free publishing - More carbon census

This article was originally posted with a long explanation, but we decided that all you really need to get the point is in the picture above. Enough said?

We could have saved sixpence ...

"Mr Rooney, we could have saved sixpence. We have saved fivepence. But at what cost?" - All that Fall, 1957

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Open publication - Free publishing - More carbon census

This month the government published our latest national CO2 statistics. They are quite interesting to look at, you can read the full press release here or just have a quick look at the chart above.

The headline is that CO2 is going in the right direction and everyone is rather pleased. In total we seem to have cut our national carbon footprint by 28%. That's the kind of good news we like to hear, if things are indeed what they seem.

But of course, things are not what they seem. The first big sleight of hand is to have excluded from the data the only 2 major sectors where carbon emissions are growing massively: shipping (up 17% since 1990) and aviation (up 109%). When these are included, the total UK saving falls to 25%.

But 25% is still good right? Well, it sounds good, but what's strange is that a big chunk of this saving (about a third of it, actually, or about 8% points) has been delivered in the last two years. And because the reporting is all a year in arrears, that means between 2007 and 2009. Hmmm. Can anyone think of anything that might have happened from 2007 to 2009 that would have reduced our carbon footprint by about 8%?

So what are we left with? When you include the boats and planes that refuel in the UK and allow for the recession we've just been having, well then you're left with about a 17% saving over 19 years, or about 0.9% per annum. Somehow that doesn't seem so exciting to me.



Here is the data table as published under, I believe, Kyoto reporting agreements. You'll notice it doesn't include shipping and aviation, we had to dig those out of a footnote to come up with the chart above.

Zero carbon homes - good policy, bad politics

Budget day today, and big news on Zero Carbon Homes. The best summary so far was from our friends at UK GBC, who said this at 5.30pm, when all the shouting died down:

“In the space of two weeks, this government has gone from a firm commitment on zero carbon homes, to a watered down policy. A zero carbon home will no longer do what it says on the tin. The world leading commitment that new homes would not add to the carbon footprint of our housing stock from 2016 has been scrapped despite a remarkable consensus between industry and NGOs in support of it. ... it is a backward step by a government that wanted to be seen as ‘the greenest ever’.” 

So, a bit of a surprise then? After all, it was only in February Grant Shapps had said "the commitment to Zero Carbon remains in place - there's no ambiguity about that" and then on 8 March, just a couple of weeks ago, The Carbon Plan from DECC was still saying things like "the government is committed to ensuring that new-build homes are zero carbon from 2016 and do not add extra carbon dioxide emissions to the atmosphere". So we might have been forgiven for thinking this one was in the bag, right?

But actually, I think not. It was inevitable that the Zero Carbon Homes objective would be watered down in some way, and here's why: this was a policy which genuinely seemed to say "let's incur cost now, so we can create benefits later - we may not be around to enjoy those benefits ourselves, but let's create them anyway, just because it is so important."

Well, I actually quite like the sound of that. And so do a lot of people. But not most people, and what most people seem to want at the moment is growth and less red tape. So from that point of view, Zero Carbon Homes was a good policy with bad politics - and relaxing it was, well, a bad policy with good politics.

Tant pis.

The electric blanket is back (article)

OK I admit it, I was wrong about electric blankets. I misjudged them. I always thought they were a bit frivolous - you know, the whole thing about not using useful stuff like electricity just to keep your toes warm. But then I realised something.

People use electric blankets because they are cold at night. If you are not cold at night, then pretty obviously  this particular posting is not about you. But what about if you are cold at night, and you don't have an electric blanket? What do you do then?

Perhaps you knit yourself a pair of bedsocks and go to bed with a nightcap. But more likely these days, you pop downstairs and turn up (or turn on) the central heating. Or you pop to B&Q and buy a cheap portable heater for about £30. (Of course, if you leave it on overnight it'll only take a few weeks to have spent more running it than it cost you to buy.)

Anyway, if those sound like things you might do, then read on. You're a person who should have an electric blanket, and here's why:

• You can get a decent one now for £35
• Leave it on overnight, it turns itself off in the morning
• In a 12 hour night shift, it eats only 0.25 KWh of energy ...
• ... costing you about 3p in total

Loyal readers will remember, that's about half what it costs me to mow the lawn for 20 minutes. And doing all the calcs, the total carbon impact over 12 hours is about the same as running a 22KW condensing gas boiler for 3 minutes. So the choice is yours: snug and warm all night for 3p, or a 3 minute blast of heat?

On that basis, and in honour of Chinese New Year, I'm making 2011 the Year of the Electric Blanket. 

"Insulation is sexy" (Who said that?)

Somehow I managed to miss this whole thing, almost a year ago exactly today. So perhaps some of you had missed it too? If so, watch and enjoy!

(Hint: Use the slider to skip ahead to 1 min 50 secs and just watch the last 20 seconds or so. That's all you need!)

What's it worth to turn off the escalators?

Today I passed through City Thameslink tube station at around 11am. There was nobody else there, but the escalators were all running. It made me think, shouldn't these all be on a stop-start system so they only run when people are there to go up and down them?

Here's the math. If you could stop all escalators on the tube from running 25% of the time, you would offset the CO2 produced by about 750 houses.

For comparison, if you wanted to provide renewable electricity for 750 houses, you'd need something like the micro hydro station at Garbhaig (see below) which cost about £1 million quid to build. So my thought would just be this, next time we have a million quid burning a hole in our pockets, let's put stop-start on the escalators instead of building another power station in the beautiful Scottish highlands.

Photo is from Roddy Smith and geograph. Here's the math if anyone wants to follow it through:

• A typical large underground escalator will have a 7500 W motor.
• There are 422 escalators in London tube stations.
• So to run all the escalators on the tube for 1 hour you need 3165 KWh of energy. 
• 1 KWh of energy creates about 500g of CO2 at average rates for the grid
• That's ~1.5 tonnes for all 422 escalators running for 1 hour
• You could perhaps save 6 hours running time per escalor per day
• That's ~10 tonnes CO2 saved per day or 3650 tonnes per annum
• The average UK house emits about 5 tonnes per annum
• So 6 hours saving per day for 422 escalators = 730 houses

It costs 6p to mow the lawn

This weekend I cut the grass with an electric Flymo.

It took 20 minutes and the flymo has a 1500W engine, so I reckon that I

• used 0.5 KWh of energy
• created 250g of CO2
• spent about 6p.

All in all, a good deal for me. I could have used an old fashioned manual mower and saved 6p, but I thought about it and I didn't want to. So what's my point? Well, I suppose the first is just that consuming energy * is not wrong, in fact it's very helpful. We're lucky that it's so easy to get your hands on some when you need it, even for everyday things. The enemy is waste, not usage, so although we do like the novelty of things like the No Impact Project, we're not really in the same camp.

I suppose the second point is just it should be easier to understand what you use. The math on this really isn't so hard. I'll post the methodology one day soon so everyone can have a go.

* OK physicists, don't all start yelping - I do know that I didn't really consume the energy, I just converted into other things, like noise and heat and grass clippings, which I suppose embody the kinetic energy required to get the blades of grass off the lawn and into the collector. But you can't say that kind of thing on a blog or it slows you down.

Lightbulb propaganda from the EU

Who'd have thought it? Some reasonably entertaining lightbulb propaganda from the EU. Very Batfink (those of a certain generation will know exactly what I mean by that).



The source for this one is Philip Sellwood's blog at The Energy Saving Trust.

October 2010: Chart of the Month

(Looking for the September Chart of the Month? Click here )

At this time of year, everyone is turning the heat on.

I've already written about how we're also turning the heat up. I used some research data from BRE to show that we've been cranking up the thermostat for about 30 years now, and as a result the average temperature inside a British home has gone up from about 13°C in 1970 to about 20°C today. As a result, I said that Britain had gone soft.

But that's only half the story. The truth is, Britain has gone very soft. The part I was missing out is what has happened to the temperature outdoors over the same period.

So guess what? It turns out that, using a more or less accepted method for measuring these things, it is a lot warmer these days than it was 40 years ago - warmer, that is, in the sense of how many days a year you'd need to turn the heating on.

Have a look at the chart below and you'll get the picture. There are about 10-15% fewer heating days per year than when our parents were our age.

Conclusion? We need less heat, but we are using more. If you can figure that one out, please post a comment below.

(Click on the image to enlarge the view.)

The raw data is from the Met Office, although access is only after an authorisation process. And here is a bit more on the methodology for Heating Degree Days. In the chart, I have taken a simple average across all UK weather stations and shown the hi/lo bands in the shaded area.

We should charge electric cars at petrol stations

Just a short post to link to my article on electric cars in the Guardian today. Seems to have caused a bit of a stir - in any case, it currently has the second highest number of comments on the environment pages, just behind "Live online: Post your questions to No Impact Man".

Hard to compete with that, I guess ... but let's see if we can catch up by tomorrow morning.

September 2010: Chart of the Month

For reasons that don't bear explaining I have found myself looking into the latest government data on light bulbs. It was quite an illuminating exercise. For instance, I learned that we have cut our energy usage for lighting by 4% in the last 20 years, although on average the light bulbs we use are 43% more efficient. Hmmm, something up with that. The explanation must be that there are more of us, and we have more bulbs each. I chewed through the data and sure enough, the picture is as follows:

(Click on the image for a full size view)

To me, the column of interest in this chart is the third. It shows that we're each using more light bulbs, which is weird. But sure enough, that's exactly what we're doing. Think of a classic kitchen refurb: you take out a 100 watt centrally suspended bulb and replace it with 8 or 10 halogen spotlights, at 35 or 50 watts each. So the total energy requirement triples, at least. Sometimes it quintuples. There are now 170 million halogen lights in UK homes, more than the total number of energy saving light bulbs in the whole country.


Some people hope to solve this problem with LED lights, but I am not convinced. A 4 watt LED from Philips costs £22, compared to 99p for a 50W halogen spotlight . The LED lasts 20 times as long, and at 10p / KWh I estimate the cost of ownership is 6 times less per hour the bulb is used. But since the halogen spot only costs 0.5p per hour, and produces nearly 10 times more lumens  than the LED version, I'm not surprised if most people just can't be bothered with the calculation.


As usual, the source data is here for anyone who wants to check the maths. But more interesting than the raw data is the moral of the story: to make the kind of reductions in energy usage that we are currently targeting, we need the third column of this chart to start working for us, not against us. In this example, we need to stop ripping out low energy solutions and replacing them with high energy solutions. It just doesn't make sense. Perhaps we should introduce a tax (or a pox!) on halogen spots.

Tax breaks for fossil fuels worth $9.1 billion

You couldn't make it up! A report from the OECD shows we're spending $9.1 billion on tax subsidies for fossil fuels. That's about $7.50 / year for each of us, just in the few selected industries that the report has looked at.

They're still working on figuring out the total, which is likely to be much larger. See the helpful comment below from Ron Steenblik, one of the authors.

Similarly, The Global Subsidies Initiative (an interesting institution in itself ...) suggests that fossil fuel subsidies outside the OECD are worth around $400 million, or getting on for $15 per person every year. As shown in the table, that's nearly 10 times the total subsidy available for renewables.

Finally, the OECD team has also estimated that removing subsidies to fossil fuels across all developing and emerging economies (I think this is the region where they have the best data) could cut global greenhouse gas emissions by 10%. And as we've seen before on this blog there are not many policies with that kind of potential.

Click here for the report this table comes from.

Vive la France!

Congratulations to France, which has de loin the lowest per capita CO2 emissions in the G8. Good news for those who think the future is nuclear. Of course some of us think that the future will not be nuclear. If anyone has a G8 league table of hazardous waste per capita please post the link.

PS I am guessing France benefits from a bit of warm weather too, from a quick look at the Canada column. The dataset comes from here if you are after the source.

We're saving £5 of energy a year - that's all

In March we posted that UK residential CO2 emissions were 500 years off target. Apologies. It turns out that we are in fact only 369 years off target - as shown below. The trend rate of improvement since the year 2000 is 0.4% per annum. In other words, since there are 27 million households in the UK, we're cutting our actual CO2 emissions by about 25 kg per household per year. 

Another way of looking at this: the total impact of all UK energy saving policies is about £5 of energy saved per household, per annum. Now, that's not a figure you'll hear quoted very often in the House of Commons.

Introducing the Carbon Census Rule of Thumb

How much power do you use when you're not using any power? Surprisingly, not zero. Take my house for example: it's a quiet Saturday afternoon, the family has gone out and everything is turned off, but our power monitor is reading 170 watts. How so? After 5 minutes poking around I found the culprits: microwave, radio, TV, DVD and a list of other things.

These devices draw a tiny amount of power, but they draw it all the time. That's the problem. So I spent another 5 minutes figuring out how much this 'background demand' is costing me. According to a really rather elegant coincidence, it turns out that 170 watts of background demand will cost about £170 a year. That's about 1 tonne of CO2 or 30% of the average UK electricity bill, just for stuff I'm not even using.

Let's call this the Carbon Census Rule Of Thumb: 1 watt of background power costs £1 a year.

(Interested in why this works? There are about 10,000 hours in a year, and a kilowatt hour of electricity costs about 10p. Well, just under 10,000 hours actually and just over 10p, but the rounding cancels out making the answer nice and easy.)

Time to Reverse Pricing

So, what to do about the fact that household CO2 continues to increase? We posted a statement of the problem yesterday, so today we post a suggestion on what to do about it. We think the government should require that domestic energy prices increase as you consume more energy, not the opposite as happens at present. Look at the charts: the left hand side shows how electricity tariffs work today, the right hand chart shows how they would work under reverse pricing. The average price is the same for the average user (4-5 MWh / year), but the marginal price would be 2 x higher - halving the payback time of a typical energy saving investment.

You can read more in our article on this in The Financial Times, or click here to download a more detailed explanation of the idea. We would welcome your comments!

What is a tonne of CO2?

About as much as

• 100 trees can absorb in a year 
• Driving across America in a car 
• A 10,000km long haul flight, per passenger
• £175 of gas and electricity at current UK prices

The Carbon Trust publish some useful conversion ratios for this kind of thing. We use a figure of about 10kg per tree which is widely quoted on the internet; the United Nations Environment Programme puts it at about 12kg a year, but 10 kg / tree (or 100 trees per tonne) is a pretty good rule of thumb.

How much CO2 can I save?

Well, here's the answer from all properties in the Carbon Census to date :

On average a UK household can save 2 - 6 tonnes of CO2 each year by implementing all of the measures identified in an official Energy Performance Certificate. About a third of the saving can be achieved with relatively cost effective measures - lighting, insulation, thermostats, heating system and so on - and about two thirds from more expensive improvements such as installing solar thermal hot water, solar panels or solid wall insulation. That said, solar panels are one of the more cost effective investments now that feed-in tariffs have been introduced. A typical installation saves about 1 tonne of CO2 per household per year.