Wednesday 22 December 2010

10:10 performance - deeply technical stuff!

In my first post of 2010, I set the target for my home's 10:10 challenge - to cut our domestic emissions to 4.5 Tonnes CO2-e by Christmas eve.  This required our annual energy use to drop by 10%, to 4,770kWh electricity and 12,655kWh gas.

And the results are: SUCCESS with electricity but FAIL with gas.  I am disappointed with this because, despite the cold and snowy weather we had in February, our moving annual total gas consumption was 13,000kWh from February to May and it hadn't risen much over the summer.  It had crept up to 13,600 by mid-November and I was determined to keep the thermostat turned down but this made no difference when one week of snow was followed by our current, much harsher freeze.  In the last four weeks of Arctic weather, our annual total gas usage has jumped to 14,850kWh.

My friend and neighbour, Vincent Jansen, has just introduced me to the concept of degree-days.  The Environmental Change Institute at Oxford University run the i-measure website, where you can benchmark your home's energy use and emissions each week.  They also publish tables of heating demand for buildings, measured at a number of sites around the country - available here.  These record the effective temperature difference that has to be maintained in buildings, in units called degree-days.  You can plot these weekly or monthly data sets against your home's heating energy usage to see how much benefit your insulation improvements or boiler upgrades have given you.  As you can see, the correlation between degree-days and gas usage in my home is remarkably strong.



Each record has a columns of degree-days recorded against a range of reference temperatures and it is important to choose the appropriate reference temperature for your building.  15.5°C is traditionally used for homes and offices (and 18.5°C for hospitals) but my records fit closest to the 14°C curve.  I have split the difference and used a base temperature of 15°C.

If you plot a building's energy use against degree-days, the line is called the performance line and the slope of this line is the building's energy loss rate.  Here are three separate performance lines for my family's home in 2008 (red), 2009 (blue) and 2010 (green).  The slope of the green line is noticeably less than the blue and red, suggesting that the extra-thick loft lagging I added last autumn has been of some benefit.


So the bottom line is that I missed my 10:10 target for home heating energy but, given the extreme weather we are experiencing this month, I could quite well have used 10% more gas than I have done, if it weren't for the extra insulation that I put in to meet my 10:10 commitments.

What about the 'leccy?  You may recall that I fitted LED lights in the kitchen and in the bedrooms.    I also switched my tower PC off last Christmas and replaced it with the amazing Fit-PC 2 net-top computer, running on just 8 watts.  The result has been remarkable.  Our moving annual total usage has dropped smoothly throughout the year and is almost on target, at 4798kWh.

One last picture shows my home's cumulative gas and electricity use through 2009 and 2010.  The effect of our prolonged cold spell is strikingly clear when this year's gas usage jumps ahead of  last year's at the end of November.  Nationally, this must have led to a huge surge in energy demand, emissions and customers' bills.



So far, I have neglected the carbon-intensity of my electricity provider.  In calculating my home's carbon emissions, I use DECC's national average carbon-intensity of 430g CO2 per kWh electricity.  However, as a British Gas customer, my electricity has the lowest carbon-intensity of any of the big 6, at 371g CO2 per kWh supplied.  If I recalculate using the British Gas carbon intensity, my home emitted 4.6 Tonnes CO2 for the year to Christmas Eve 2010.  So I can console myself that, despite missing my target for gas usage, our overall carbon emissions are almost where I had hoped.

For the broader aspects of carbon footprint, such as diet, lifestyle, shopping and travel, I don't have any hard and fast measures.  If we all eat less meat and dairy, buy more local and seasonal food, make our clothes and electronic gadgets last longer and keep our feet firmly on land (or water) when we take our holidays then I suspect we'd make a big dent in Britain's climate-changing carbon emissions.  The transition to a sustainable economy is going to be a major theme of the coming decade and I hope many people here and around the world will jump at the chance to make life better for all the generations to come.

Tuesday 14 December 2010

What colour Christmas are you dreaming of?

My inbox is filling up with seasonal cheer and helpful advice, generally around the theme of a enjoying a jolly green Christmas.  For instance, this beautifully wrapped cracker from Global Action Plan and this charming range of e-cards from Friends of the Earth.

But what is the real impact of Christmas?  Beyond the original, spiritual meaning(s), our festive season clearly retains a central cultural role in bringing families together.  Unfortunately, this leads to the seasonal binge of over-consumption - from wrapping paper to decorations, from turkey to more turkey and from overcooked veg to repeats on TV.  As a vegetarian household, we are at least spared the excesses of turkey - but we do have to endure our share of repeats.

Recent press coverage suggests that most families are letting their heads rule their hearts and agreeing budget caps for presents, in response to the financial pressures that we are all feeling this year.  But there is also the danger that, when times are hard, we cut back on our charitable giving.  We may not want to give a goat, indeed we're being told that a goat might be a burden for some families and their local environments, but the Good Gifts range has presents that will appeal to everyone.  Rather more personally, KIVA and Deki allow you to lend a little money ("microloans") to an individual family in the developing world, for a specific purpose.  Microcredit was pioneered by the Grameen Bank (whose founder, Muhammad Yunus, won the 2006 Nobel peace prize for this) in Bangladesh and it has spread rapidly around the developing world because of its amazing power to change the lives of the ultra-poor.

KIVA and Deki both allow you to give gift certificates to your loved ones, who then have the pleasure of selecting the projects and the people that they wish to lend to.  Almost all the projects repay their loans and the lender is then free to withdraw their money or to lend to another project - meaning that the credit "revolves" to help one family after another.  It could be a gift for life, not just for Christmas.

One of the perennial debates during Advent is the merits of real vs. artificial trees.  When our children were young, we always went to buy a freshly cut tree from the nearby Crown Estate in Windsor Great Park.  About 10 years ago, my uncle decided to throw out his old, artificial tree, and offered it to us.  Since then, we have changed our annual ritual to a journey into the attic to bring down this majestic fake fir and I was delighted that, last weekend, my daughter put the tree up and decorated it all by herself while mum and dad had a leisurely lie-in!  The moral of this tale has to be that, whatever the relative merits of real or artificial Christmas trees, the greenest choice has to be the artificial (or real, if potted and movable) one that you carefully store from year to year.


My top tip for December shopping?  B&Q Everyday Eco loft insulation - mineral wool top-up at £3 for 5.5sq. metres.  That's the cheapest it's ever been so snap it up while it's going!  Merry Christmas everyone.

Thursday 2 December 2010

Will Britain ever be sustainable?

Walked through Hyde Park in the snow last night to attend this fascinating debate at the Royal Geographical Society in Exhibition Road (next to the Albert Hall).  The presentations and the discussion were videoed and are available to watch online, here.  Author and sustainable business advisor, Peter McManners, has published another thought-provoking take on this debate here.

Sir Stuart Rose (of M&S fame) talked about positive action from business and was credible, upbeat and sharp.  He recognised that most of the hard work lies ahead and acknowledged the paradox that, right now, it's business leaders rather than consumers who are leading the transition to sustainability.  When asked what can WE as individuals do to make Britain sustainable, Sir Stuart replied with admirable candour,
"Eat everything in your fridge (I eat lots of out-of-date stuff) - keep your clothes for longer (they're much tougher than you think) and use less."  Good on him!  The debate's chair and Guardian editor for Environment and Sustainability, Jo Confino, has reported Sir Stuart's comments in more detail here.

Hilary Benn, MP, Shadow Leader of the House of Commons and former Minister at DFID and DEFRA, took a very different tack from our nation's premier shopkeeper.  He highlighted issues of unsustainable consumption in our modern world, from the inequality of food supply (1 billion overweight/obese and another billion going to bed hungry tonight) to the impoverishment of biodiversity.  He noted that scaring people is bad politics and asserted that we must lead the way to sustainable lifestyles in Britain with a dream, not a nightmare.  Most provocatively, Hilary told us that Government can't do things alone: radical change involves all of us.  Where were the public and NGOs during the fuel price riots, he asked?  The Labour government looked all round for support for their environmentally-driven fuel price escalator but found not a single voice.

Mr Benn concluded that others must show leadership, especially when the going gets tough.  As you might imagine, the audience returned to this point during questioning.  Rad Hart-George asked him whether the transition to renewable energy was too big for citizens to lead themselves and, if so, would the Government step up to make it happen.  Benn responded with the importance of citizen-generated renewable energy through the Feed-In Tariff and Rent-a-Roof schemes.  Of course, this was not intended to be a technical discussion but I didn't get the impression that the Shadow Leader of the House sees any substantial barriers to the decarbonisation of Britain's energy sector, which I found deeply troubling in the light of Monday's "Countdown to 2020" conference.

A very creative and inspiring presentation followed from Andy Hobsbawn, founder of Green Thing, the not-for-profit organisation behind the outstanding  website, Do the Green Thing.  Why do people queue all night to get the latest iPad but can't be bothered to switch a light off when they leave the room?  These activities live in different brain areas, he said, one associated with pleasure, desire, reward and the other with admin, chores and to-do lists.  Great creativity transforms things - it's a "meme-maker" and leads to insanely desirable tools for self-expression, like the iPad.  Andy applies great creativity to making the simple, sustainable choices attractive - like going for a walk and turning off a lightswitch.  He showed us his solutions to these challenges - they were all lovable, quirky and fun, making environmentally sustainable choices and behaviours desirable.

A "clean coal" developer asked the Panel whether his penchant for frequent air travel makes him into a "walking contradiction".  In response, Hilary Benn talked of the "complex ecology of modern existence" and the interdependence that makes it hard for countries to act on their own  - whereas Andy Hobsbawn said, "Think, act.  Get information and then do it right.  Change the people around you."  In that moment, I saw where the clear vision of a sustainable future is going to come from.  While business leaders will work  pro-actively to make their products and services sustainable, to protect their future earnings, politicians need the likes of Andy Hobsbawn to wake up the electorate - because democratic Governments can't and won't act until their constituents demand that they do.  As Mr Benn said, radical change involves all of us.

Post Script:
This 5-minute video from the American Post Carbon Institute just landed in my inbox, thanks to Eco-Tube. I think it encapsulates what Hilary Benn tried to convey in his opening remarks and I am inspired by the narrative.  More creative communication than creative solutions, it makes the point that we are heading for a post-carbon future either way. By acting now, we can make it sustainable and beautiful. Do nothing and it will be ugly and terminal.  Last night's debate was really about how we get this message across to people, effectively and immediately.