Tuesday, May 22, 2007
A lot has been written on energy dependence. I'm convinced that we should be producing energy in as many different ways as it is ecologically feasible to do. There is no method of energy generation/collection that has zero pollution. Although some methods shine brighter than others, many just move the pollution to areas where coyotes don't vote. The electric car isn't much better than a gasoline engine if the electricity is generated by burning coal out in the boonies somewhere. Large hydro-power generation stations in Canada flood large areas of land (e.g. the Lower Churchill Hydro Generation Project flooding 121 square kilometers of land area for 2.8 GigaWatt capacity). There are tradeoffs to everything.
Strengths and Weaknesses
Along with their weaknesses, each method has some strengths.
- Hydro power generation (with dams) allows you to defer energy generation (i.e. store it) until you need it by raising the water level behind the damn. In this sense, it can act like a ginormous battery or capacitor.
- Wind power is fickle. Although many locations can provide necessary windspeed to make them worthwhile, if the wind isn't blowing, there's not a damn thing you can do about it. No power for you! Otherwise, wind power is pretty clean, except for the noise and visual pollution.
- Solar power (electrical), like wind power, only generates electricity while the sun is available. It is a "now or never" type of energy source - if you do not harvest it now, you will never will. As such, any but the smallest photovoltaic operations use a power point tracker to dynamically keep the load at the point of maximum power transfer (or 50% electrical efficiency). Actually, a Heliostat can be used to store solar power in the specific heat capacity of liquid sodium, allowing it to continue to generate electrical power long after the sun has gone down. Both methods require large land area for solar collection. At sea level, the sun provides approximately 1370 Watts per metre of incident energy.
- Burning Coal sucks, but sometimes that's all you've got.
- Human Powered Energy (e.g. riding a bicycle hooked to a generator) may be optimal in terms of energy efficiency (this is a guess), but you'll need a pretty big child-energy generating sweatshop to light up Vegas. People just don't have enough oomph to meet world heat, recreation, and manufacturing needs.
- Nuclear Power Generation holds a lot of promise for the future when we can get to clean fusion, but for now we're stuck with mind-numbingly polluting fission. (and on a tangent, I find it strange that a country with enough fossil fuels to last them for over a hundred years and an stated agenda of wiping out another country feels it needs a nuclear program ASAP)
The list goes on and on. The point is that we should be attempting to optimize the "cleanness" of our energy grid power generation. With multiple hydro generation dams in the grid, excess energy generated via the greener methods can be stored as gravitational potential of water, running it back out to generate more power during peak times. (again, this works just like a huge freakin capacitor in a regulator) In some places around the world, locals can even sell their locally produced energy back into the grid.
I predict that eventually we are going to run into a big power crunch. As in some places already, there will be different electrical power rates for peak and off peak times. I haven't calculated one, but there will be some magic number when it will be economically feasible to cheaply buy grid power in the off-peak time, store it, then sell it back into the grid at the peak time. We're going to reach this point somewhere between when power rates are crazy-high or effective storage systems become incredibly cheap.
When this happens, we will be ready for the most robust power grid in history! When it becomes economically feasible for the buy-store-sell electrical model at the individual level, everybody wins! First, the person buying and selling the grid power makes money doing it (this is the economically feasible part). This person is happy. Second, the power company sells their power to you once at a profit, then makes profit again when they re-sell the power sold back to them at the peak time. They are happy. The power company is especially happy since you have also effectively increased their power storage capacity an incremental amount. When lots of people on the grid start doing this, the result is a huge massively parallel distributed power storage grid. The distributed power storage now in the grid acts like a huge Uninterruptible Power Supply (UPS). If the power goes out, we'll have enough backup capacity for a little while, even if local segments are isolated from the larger grid! I don't see how this is anything except win-win-win for everybody involved.
Wouldn't it be ironic if it were a power shortage and monetary greed that allowed the conditions necessary for society to create a more robust power grid?
Burton MacKenZie www.burtonmackenzie.com