The Green Gap

In the Cold War, we feared a Missile Gap was a strategic weakness. Nowadays, we must awaken to the fact that the Green Gap is true strategic weakness: the nations whose economies will thrive in the coming years will not be those with the biggest factories, but those with the most sustainable, efficient, and ecological markets. What we require is a Strategic "Green Reserve" of ecological design to weather the coming changes that both climate and resource scarcity will force on the international economy.

Sunday 18 December 2011

I said here that a solar power system to provide enough heat and power to supply a single house in Calgary would cost in the neighbourhood of $150,000. I was wrong.

Calgary has an average of over 2400 hours of sun per year.
This package of 20 Canadian Solar solar cells costs  $10,936.00.
It produces 20x240v of power, times 2400 hours of sun, equals 11520 kWh/year.
That's more than enough (by about a third) to power an average detached home in Calgary.
With 40 more panels, the same home could be heated, according to the StatsCan numbers in the referenced article.
Amortised over the 25 year warranty, that's $192.91 per month at 5% interest.

Bundled with the cost of your own mortgage, that would be negligible.

This nifty website let's us compare costs. For 11520kWh/year, the price would be somewhere around $100 per month in Calgary. For heating a home, Enmax charges $6.59/GJ. At an average of 140GJ/year for a Calgary home, that's about $77/month in gas heating.

Assuming no increases in gas or electricity price over the next 25 years....

...OK, really, stop laughing....

...assuming no increases in gas or electricity price over the next 25 years, solar is actually competitive. It is ABSOLUTELY competitive when comparing to electricity price alone. As a matter of fact, if you own a detached house, this basically means that you're losing money by not getting a solar system. How much are you losing? Approximately (assuming amortization over 25 years at 5% interest) $35.70/month, or $10,710 over the life of the system - again, at current market rates for electricity.

For fun... we are currently buying 900MW from BC and Saskatchewan and that is likely for the peak business hours of every day. It would take 187,500 houses equipped with this solar system to replace that amount of generation... so it's not really possible... but replacing ANY part of that generation capacity is the elimination of an expenditure for the utility. Enmax credits homeowners back for the electricity generated through microgeneration, but  am certain they take a good margin for themselves. Not only is it expenditure avoidance, it's a revenue positive proposition.

The City of Calgary, which wholly owns Enmax, should be taking this up with Calgarians far more vigourously...

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