Carbon Commentary » domestic http://www.carboncommentary.com A critical appraisal of issues in the move to a low-carbon economy Fri, 18 Jul 2008 16:56:50 +0000 http://wordpress.org/?v=2.3.3 en Energy efficiency of home phones http://www.carboncommentary.com/2008/03/22/80 http://www.carboncommentary.com/2008/03/22/80#comments Sat, 22 Mar 2008 15:32:32 +0000 Chris Goodall http://www.carboncommentary.com/2008/03/22/80 BT announced that it was bringing out a new range of home phones with much improved energy efficiency. The claim is that ‘the new handsets boast power units designed specifically to consume around half the power of previous units’. BT said that almost all its extensive home phone range would contain the new energy-saving technology by mid-2008. Its press release gave very precise figures for the amount of CO2 saved – comparing the savings if all home phones incorporated the new technology to taking ‘57,000 cars off the road for a year’.]]> BT low energy power supply phone
BT announced that it was bringing out a new range of home phones with much improved energy efficiency. The claim is that ‘the new handsets boast power units designed specifically to consume around half the power of previous units’. BT said that almost all its extensive home phone range would contain the new energy-saving technology by mid-2008. Its press release gave very precise figures for the amount of CO2 saved – comparing the savings if all home phones incorporated the new technology to taking ‘57,000 cars off the road for a year’.

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]]> http://www.carboncommentary.com/2008/03/22/80/feed Trends in UK domestic electricity use http://www.carboncommentary.com/2008/02/20/76 http://www.carboncommentary.com/2008/02/20/76#comments Wed, 20 Feb 2008 17:32:04 +0000 Chris Goodall http://www.carboncommentary.com/2008/02/20/76 In most countries electricity use is rising. The increase is gradual in developed areas, averaging only 1 or 2% a year. In the UK, the pattern was similar but recent years have tended to show declining growth rates, partly perhaps as a result of increasing prices.

One of the most interesting features of recent UK trends has been the flattening in electricity use in the home. This change is somewhat surprising. Improvements in home energy efficiency, through such things as the use of compact fluorescent light bulbs and high quality white goods, have usually been thought to have been outweighed by increases in the number and power use of consumer electronics. Large LCD TVs are, for example, much heavier electricity users than the old-fashioned TVs that they replace. Today’s games consoles are much more powerful than ones of five years ago.

So the reasons are not clear, but monthly year-on-year growth in domestic consumption of electricity has fallen to below zero in the last year or so. Is this a temporary change brought about by the steep increases in prices over the period 2005-6, which will be unwound when people get habituated to higher costs? Or is this a real change in household behaviour?

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]]> http://www.carboncommentary.com/2008/02/20/76/feed Zero-carbon homes may look nice but they aren’t cheap http://www.carboncommentary.com/2008/01/14/69 http://www.carboncommentary.com/2008/01/14/69#comments Mon, 14 Jan 2008 16:51:55 +0000 Chris Goodall http://www.carboncommentary.com/2008/01/14/69 The Lighthouse by Potton The Lighthouse by Potton Carbon Commentary has visited two sites to look at the costs of building houses under the new rules (not yet mandatory) established by the Code for Sustainable Homes (CSH). By 2016, all new UK homes will have to have no net carbon emissions (‘Level 6’) and the implications for construction techniques are profound. Today, most homes are built to about Level 1, or possibly 2. To get to Level 6 will require huge changes in how houses are built, heated, and ventilated. And they will need expensive renewable energy technologies built into the home as well. At Wimpey’s 145-home development in Milton Keynes, construction costs of houses at Level 3 are running at ‘100-110%’ more than standard. The self-build company Potton is offering a Level 6 design (one of the first in the UK) for an even more expensive £180 a square foot, up from about £75 for a standard Level 3 model. This takes the construction cost of a standard 1,000 sq ft (92 sq metre) home up from £75,000 to £180,000. Much of the increment comes from the need to install large amounts of renewable electricity generation. Some of the cost premium over today’s badly insulated homes will eventually erode as builders get better at building air-tight houses. But we shouldn’t be in any doubt about the huge implications of the CSH for builders, landowners, and buyers.]]> The Lighthouse by Potton The Lighthouse by Potton

Carbon Commentary has visited two sites to look at the costs of building houses under the new rules (not yet mandatory) established by the Code for Sustainable Homes (CSH). By 2016, all new UK homes will have to have no net carbon emissions (‘Level 6’) and the implications for construction techniques are profound. Today, most homes are built to about Level 1, or possibly 2. To get to Level 6 will require huge changes in how houses are built, heated, and ventilated. And they will need expensive renewable energy technologies built into the home as well.

At Wimpey’s 145-home development in Milton Keynes, construction costs of houses at Level 3 are running at ‘100-110%’ more than standard. The self-build company Potton is offering a Level 6 design (one of the first in the UK) for an even more expensive £180 a square foot, up from about £75 for a standard Level 3 model. This takes the construction cost of a standard 1,000 sq ft (92 sq metre) home up from £75,000 to £180,000. Much of the increment comes from the need to install large amounts of renewable electricity generation. Some of the cost premium over today’s badly insulated homes will eventually erode as builders get better at building air-tight houses. But we shouldn’t be in any doubt about the huge implications of the CSH for builders, landowners, and buyers.

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]]> http://www.carboncommentary.com/2008/01/14/69/feed Household batteries http://www.carboncommentary.com/2007/12/12/63 http://www.carboncommentary.com/2007/12/12/63#comments Wed, 12 Dec 2007 17:30:56 +0000 Chris Goodall http://www.carboncommentary.com/2007/12/12/63 Inventions that take the breath away with their simplicity and elegance are rare. The new rechargeable batteries from USBCell qualify for this honour. As their name indicates, they are AA batteries that are recharged by the USB port on a laptop or other powered device. They are not cheap, but will repay the investment by being far easier to recharge than conventional rechargeable AAs. The carbon savings from these batteries are not large. My calculation is that they might save 10kg of CO2 a year in a household full of portable devices. But they will, of course, reduce the waste going into landfill. The company that makes the batteries has won some important awards for its innovation. More importantly, it also has some extremely interesting views on the evolution of home electricity demand. It correctly points out that a larger and larger fraction of home energy is used in 12V, not 240V appliances. We waste a lot of energy switching 240V AC down to 12V DC. Its next products include a box that will allow all DC devices (phones, handheld consoles, laptops) to be efficiently charged. Eventually, it will be possible to use cheap(-ish) solar power collectors to charge all the battery DC devices in the home. The savings in carbon would be worthwhile (but probably outweighed by the purchase of one extra TV).]]> Inventions that take the breath away with their simplicity and elegance are rare. The new rechargeable batteries from USBCell qualify for this honour. As their name indicates, they are AA batteries that are recharged by the USB port on a laptop or other powered device. They are not cheap, but will repay the investment by being far easier to recharge than conventional rechargeable AAs.

The carbon savings from these batteries are not large. My calculation is that they might save 10kg of CO2 a year in a household full of portable devices. But they will, of course, reduce the waste going into landfill.

The company that makes the batteries has won some important awards for its innovation. More importantly, it also has some extremely interesting views on the evolution of home electricity demand. It correctly points out that a larger and larger fraction of home energy is used in 12V, not 240V appliances. We waste a lot of energy switching 240V AC down to 12V DC. Its next products include a box that will allow all DC devices (phones, handheld consoles, laptops) to be efficiently charged. Eventually, it will be possible to use cheap(-ish) solar power collectors to charge all the battery DC devices in the home. The savings in carbon would be worthwhile (but probably outweighed by the purchase of one extra TV).

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]]> http://www.carboncommentary.com/2007/12/12/63/feed Smart metering http://www.carboncommentary.com/2007/12/12/67 http://www.carboncommentary.com/2007/12/12/67#comments Wed, 12 Dec 2007 17:30:24 +0000 Chris Goodall http://www.carboncommentary.com/2007/12/12/67 The world understands ‘smart metering’ in many different ways. Gordon Brown used the expression in his first speech on climate change. He meant devices that give visual real-time indication of electricity consumption, largely in homes. To the UK Conservative Party (see this issue of Carbon Commentary) it means conventional meters that can record the export of electricity from a house, as well as its use. Smart meters are much more useful than either of these two definitions suggest. Their primary value will be to adjust the price of electricity depending on the level of demand. This frightens politicians because they fear the backlash from users complaining of the horrendous cost of peak-time electricity use. But if we are to increase the percentage of electricity coming from intermittent and/or unreliable sources, smart meters are a necessity.]]> The world understands ‘smart metering’ in many different ways. Gordon Brown used the expression in his first speech on climate change. He meant devices that give visual real-time indication of electricity consumption, largely in homes. To the UK Conservative Party (see this issue of Carbon Commentary) it means conventional meters that can record the export of electricity from a house, as well as its use.

Smart meters are much more useful than either of these two definitions suggest. Their primary value will be to adjust the price of electricity depending on the level of demand. This frightens politicians because they fear the backlash from users complaining of the horrendous cost of peak-time electricity use. But if we are to increase the percentage of electricity coming from intermittent and/or unreliable sources, smart meters are a necessity.

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