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EARTHFUTURE.COM by Guy Dauncey
It’s not fun being cold. Your teeth chatter, and your toes and fingers hurt. It may be no coincidence that when recent ice ages began to roll across the landscape 400,000 years ago, we learned how to make fire.
In theory, the sun gives us all the heat we need: 3,000 times more energy than we use each day. But it’s no use after sunset, or when winter strikes. Learning how to tear a branch off a tree and carry its stored solar energy into a cave must have been brilliant. Later, we learned how to make charcoal, burning the wood to get rid of the smoke, leaving a clean, glowing briquette. Charcoal burners were terrible forest destroyers, but we loved the result. It kept us warm.
For thousands of years, we hacked away at the forests. Then sometime in the 12th century, in England, the firewood began to run out. So people started using a nasty black substance called sea-coal. It made such a smell that it was quickly banned, but it was only a matter of time before everyone was using it. Coal. Ancient sunlight from ancient trees and ferns. We had discovered fossil fuels. The city air was disgusting, but oh, how warm everyone was.
All I want is a room somewhere,
Far away from the cold night air.
With one enormous chair,
Ah, wouldn’it be loverly?
Lots of choc’lates for me to eat,
Lots of coal makin’ lots of heat.
Warm face, warm ‘ands, warm feet,
Ah, wouldn’it be loverly?
(from My Fair Lady)
And then came natural gas, from plants and tiny creatures which died and sank to the ocean floor 300 million years ago. How modern! How civilized!
But how does this story end? North America’s natural gas has already started to run scarce: we’re on the downhill slope of the supply. The entire world’s gas supply will peak by 2020 and be gone by 2060, assuming we’re happy to liquefy it and ship it across the world in highly explosive tankers. It’ll be far too expensive for most of us to use long before that.
So what then: back to coal? With climate change heating the oceans and burning the forests? I don’t think so. To firewood? Not unless we want to clearcut BC. So what will we do? Electricity? Yes, it’s possible, assuming we can generate enough sustainable electricity. But it’s a very inefficient way to make heat.
How will we heat ourselves, when the gas runs out? This is a huge unanswered question that no one wants to address.
It’s easy to design a zero-energy house. Make it passive solar in design to catch and store the sun’s heat. Dig or drill down into the earth to make a ground-source heat system, and use solar photovoltaics to power a heat pump to deliver the warmth to your home. Add super-efficient windows, super insulation, and heat-recovery ventilators. Top it off with a solar hot water system.
But can we retrofit a whole city, to keep its inhabitants warm? It’s a very big question. There are no easy answers, but there are some tantalizing clues.
In Zurich, Switzerland, engineers have created a 200-metre length of sewer pipe in which the bottom of the pipe acts as a heat pump. The pipe transfers the heat into a district heating system, which supplies a third of the heat for 940 homes, saving 1,500 tonnes of CO2 a year. Where there’s sewage, there’s heat. (www.rabtherm.de)
In Sutton (outside London, UK), the Beddington Zero Energy Development heats 93 units of super-efficient, solar buildings from a biomass cogeneration plant, using chipped tree trimmings that would otherwise have gone to the landfill. (www.bedzed.org.uk)
In Anneberg, in the city of Danderyd, Sweden, engineers have designed a 90-unit housing project where the south-facing roofs are completely covered with solar hot water systems. During the summer, the heat that’s gathered is pumped 65 metres down into the ground with 100 boreholes. It’s insulated with a 3-foot layer of foam, and when winter comes, it is brought back up again to heat the homes. (www.sb.luth.se/~bon/anneberg.htm)
In Okotoks, Alberta, a 52 unit solar-heated subdivision will be finished this fall: the first in North America. The heat will be gathered on the garage roofs and pumped underground, to be retrieved in winter. It’s expensive, but it’s doable, and with mass production, the price of solar heaters will come down.
But what about our existing cities? The good news is that the sun shines everywhere, and the ground exists everywhere. With evacuated solar tubes, the sun’s heat can be gathered even under a cloudy sky. We could superinsulate and retrofit our buildings for district heating systems, collect solar heat off every available surface (roofs, walls, car-parks), and pump the heat underground to retrieve in winter.
Will it cost a lot? Yes. Will we decide to do it? Yes. Which would you rather do? Sit with your teeth chattering all winter in a house with no heat, or fork out for a permanent, sustainable, clean, silent, climate-friendly solution?
Guy Dauncey is president of the BC Sustainable Energy Association (www.bcsea.org), and author of Stormy Weather: 101 Solutions to Global Climate Change. He lives in Victoria. www.earthfuture.comGuy Dauncey is president of the BC Sustainable Energy Association, www.bcsea.org. BP’s website and contact details are at www.bp.com
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