Why we need to use energy more sustainably

My guest blog on the British Gas Customer Newsroom website.
http://www.britishgasnewsroom.co.uk/2012/01/why-we-need-to-use-energy-more-sustainably/

Two photographs illustrate the article.  The first depicts my schoolfriend, David Kidd, fitting a Navitron solar thermal heating system on my roof.  He's standing safely in a long, horizontal valley between two pitched roofs so no need for a harness.  The second shows the excellent downlights that I fitted into the bathroom cabinet recently, replacing 60 watts of halogen lights with 7.2 watts of warm white LED cabinet units from www.ledcentre.uk.com

Many people argue that we can best engage the public in climate change action using positive terms, such as money to be saved, rather than evoking fear and other negative sentiments by describing the threats of unmitigated warming.  A recent scholarly analysis of climate change communications by Jacqueline Stewart, of George Washington University, gives examples of effective and counter-productive attempts to communicate climate change but concludes only that success depends on the specific message, messenger and circumstances.

I believe people need to hear the truth about our situation - how can we care about something we aren't aware of? - but agree that this needs to be coupled with positive messages on what we can do about it.  

This guest post is my attempt to communicate the big picture on consumption, carbon emissions and consequences, together with clear proposals for personal action to reduce all three.  I am pleased that British Gas have agreed to post it on their customer website and hope that it will reach a wide audience.

Numbers not Adjectives

In the words of Professor David Mackay, we need "numbers, not adjectives" to compare, understand and manage our country's energy supplies and our own energy demands.  In this spirit, here are two charts.

The first shows my family's energy use at home each year from 2006 to 2011.  For reasons I have made clear throughout this blog, we used 52% less energy in 2011 than in 2006.

The second chart shows the costs of this energy.

Sticking to Prof. Mackay's injunction, I will simply note that, despite increases in the unit costs we pay for energy over this period, our total bill for energy in 2011 was 38% smaller than we paid in 2006.

There are all sorts of issues, from fuel poverty to carbon emissions, that this comparison does not address.  The simple point that it illustrates well, however, is that individual efforts and investments to use energy more efficiently have a real impact on our energy bills.  If my family had used as much energy in 2011 as we did in 2006, our bills would have risen by 17% over this period - despite switching to a cheaper supplier at the end of 2008.

And the carbon emissions from our energy use?  I calculate that, in 2006, these amounted to 8 Tonnes CO2.  In 2011, our annual emissions were down to 3.6 Tonnes CO2.  The total reduction over five years (2007 - 11) amounts to 15.7 Tonnes.

This may not sound much compared with, for example, long-haul flights, but we haven't taken any of those in the last five years either.  Cutting carbon makes each and every part of life more sustainable, from holidays to heating, from commuting to computing and from diet to DIY.  Oh dear, I've forgotten the Professor's advice and slipped into rhetoric so I'd better stop and leave you to do the maths.

Reducing oil consumption

Here are my thoughts on reducing our use of oil while we still have some left to play with!

New Scientist (4 July 2007, "Biorefineries: curing our addiction to oil") reports that over 70% of the oil we extract is used for transport fuel. Most of the remainder is burned for energy (and this without including natural gas, another fossil carbon) or used for roads, lubricants and waxes. Just 3.4% is used in the petrochemical industry, to synthesise all the materials we depend on in our everyday lives - e.g., plastics, cosmetics, paints and medicines. Wouldn't it make sense to cut down the 90-odd percent that is used for energy and save the oil for petrochemical manufacture? If we were to do this ahead of "peak oil" then the feedstocks that we need for the synthetic chemical industries could last for centuries.

It is comparatively easy to switch electricity generation over to renewables, including woodchip and pellet technologies used for industrial "cogeneration" or combined heat and power (CHP). Slough Trading Estate has been doing this for several years so your UK Mars Bars are made using sustainable energy. This type of biofuel makes sense and does not compete for agricultural resources with food supply. The biggest problem will be scaling up the supply of woody fuel - perhaps an argument for restoring some of Britain's native woodland cover that was displaced by farming?

It is much harder to make the switch to renewables for the transport fuel we all depend on because few other materials have the energy density of petrol or diesel. Plug-in hybrids could help, if recharged from renewable electricity, but hybrid cars today are really no more than green window-dressing to enhance the reputations of the world's largest car manufacturers, while they continue to flog Chelsea tractors, SUVs, pickups and luxury limos.

Whether it's ethanol from sugar cane ('gasohol' in Brazil) or biodiesel from oilseed crops, production of biofuels for transport displaces food production (witness the soaring price of bread). More importantly, to meet the current transport fuel demands of the developed world, biofuel would have to supplant food production entirely - and then some more!

There is an overwhelming need is to change the way we use transport - both personal and freight. That's a very tall order but nothing else comes close to providing a sustainable solution.

Energy efficiency, both domestic and industrial, offers huge prizes but is barely beginning to be tapped here in England because energy is still far too cheap. There is loads of advice available on improving our domestic energy and I will post the best links I can find to help with this. Retailers and manufacturers have much scope to cut their energy consumption but the economics will need to change before they pay more than lipservice to these opportunities. Massive hikes in the price of oil and gas would drive energy efficiency but this is not going to win elections anywhere in the world and so seems unlikely to happen before we reach peak oil.

Solar thermal power is already highly efficient - vacuum collector tubes can capture over 90% of the solar energy reaching them. Rooftops around the world should be covered in them already but - outside of Germany - they are not.

Solar electricity generation, in contrast, uses only up to 15% of the incident energy. There is plenty of room yet for technological innovation, both the physics of solar energy capture and the manufacturing processes used to produce photovoltaic panels in large quantities and at low cost.

Even nuclear fission is ultimately unsustainable because the uranium reserves are limited and the environmental and human costs of uranium mining are very high. If we could tame nuclear fusion as an energy source we would really be getting somewhere!