With Site C dam public hearings traveling the Peace Region at the moment, it is hard to avoid discussing the pros and cons of large dams. Site C is being promoted as a "clean" energy project, but as we will see, when it comes to energy, "clean" is a matter of definition.
LET IT SNOW, LET IT SNOW
First I am happy to say that by the time you read this, my 5.6-kilowatt photovoltaic (PV) array should be pumping green juice into the local grid. At the moment, however, it is covered with two feet of fresh snow, along with the entire city of Dawson Creek and most of northern B.C.
What about snow on the solar panels, you may well ask? A thick layer of snow on PV panels drops their output to essentially zero, but for a grid-tie system like mine, it doesn't matter. Here's why:
When looking at the idea of covering my roof with PV panels, the first thing I did was look at my electrical bills. Clearly, I used very little electricity in the spring, summer and fall, but a lot in the winter, mostly from my big furnace fan but also increased use of lighting.
I then measured my roof and figured out how many solar panels I could put on it, and used several on-line calculators to estimate how much power I should expect them to generate at my geographic location (Environment Canada's website has a good solar calculator).
As it turned out, my roof could generate almost enough electricity in the spring, summer and fall (when we get lots of solar up at this northern latitude) to cover the entire year. But not quite. I would have to reduce my load a bit.
That energy-pig yard light will have to go. An LED motion sensor yard light, which only comes on when I actually need it, will be a big help. (Studies are clear: motion sensor yard lights not only reduce light pollution and pay for themselves quickly with energy saved, they also provide better security!)
Then as my tungsten and compact fluorescent lights burn out, I will replace them with LED's. I will also be sure that all equipment (computers, printers, lights) will be turned off when not in use. These three simple measures should push me into a net zero electrical zone: averaged over the year, I should produce all my own electricity. When I have extra juice in the spring, summer and fall, it will be "stored" in the grid as a credit on my account, which I will then withdraw through the winter, as I need it.
So that's why snow on the solar panels doesn't matter. (And by the way, snow does tend to slide off of the slippery glass surface of solar panels, so I will produce some electricity through the winter, but that's just bonus power.)
WHAT IS CLEAN ENERGY?
Suddenly it seems that every energy source is "clean": clean coal, clean gas, clean hydro, clean nuclear. Obviously clean is a relative term. It depends on how you define it.
Personally, I define clean energy from the most common sense and straight forward point of view I can think of: energy which when generated produces no pollution. Every energy source produces a certain amount of pollution to build its own infrastructure, from coal-fired plants and hydro dams to solar panels. But if they produce no pollution during use, then to me it makes sense that they are producing "clean" energy.
No fossil fuel, by this definition, can be clean. They all burn something and produce pollution during operation. Nuclear reactors "burn" nuclear fuel and generate radioactive pollution during operation, probably the most dangerous form of pollution ever created - definitely not clean.
Solar power, wind power, geothermal power and tidal power, on the other hand, use up and burn nothing when they are producing energy, so no pollution is created. They make clean energy.
That leaves hydroelectric power. It's renewable (natural forces constantly replenish the energy source), and it doesn't burn anything to produce power, so it's potentially very clean. But is it? In the next "Watt's Happening" I will do my best to answer that question.