The true goal [of green energy] is to find the method that provides the most bang per buck in removing load from the grid.

via Brad Ideas | Crazy ideas, inventions, essays and links from Brad Templeton.

The essay is interesting, and compares the cost of solar energy production to the amount of energy that can be saved via simple conservation.   I don’t at all agree that conservation is a cheaper way to reduce energy consumption than solar is.  There are many people who are willing and able to do both, and articles like this make it seem like one should never install solar.  But, the bottom line is, if you have the discretionary income, then you should get solar, buy CFL lights, drive a Prius, install efficient appliances.  Do absolutely everything within your power to reduce your emissions!  Brad should be motivating and empowering the country to do as much as they can with their dollars!

But, Brad doesn’t address the most important issues:

What is the true cost of the emissions from dirty energy sources?

One way to begin to answer this question is to look into how much Carbon Credits cost on different markets, and how this influences the full circle lifetime cost of energy.  (See also Emissions Trading)

I don’t have time right now to do the research, but I will say that we can never know what the future cost of today’s dirty energy sources are.  (emissions data per energy source can be found here).  The cost of carbon credits vary widely from $1/Ton Carbon to $25/Ton.  As an example, burning a gallon of gas produces about 20 pounds of carbon (from epa.gov).  Using today’s prices, this adds between $0.01 and $0.25 for the cost of the emissions.   1 penny is a small cost, but 25 cents is something that would actually begin to change people’s driving and buying behaviors, and would significantly change the financial models for things like the Prius.

But, carbon sequestration techniques are in their infancy, and are currently very expensive.  Carbon capture via trees is a good idea, but as a whole, the planet is cutting down trees, not planting the, and thus, making the problem worse.  Existing “carbon offsets” sometimes use experimental techniques (like seeding the oceans with iron to stimulate algal growth) that are unproven and have unknown long term side effects and viability.  This market is very immature and we don’t know where it’s going!   And, we have yet to even talk about things like the Mercury that is burned by coal production!  How will we clean this up?  At what cost?  (Over 50% of the U.S. electricity is generated from coal! via epa.gov)

So, Brad, I challenge you to come up with an economic model for the cost of burning a gallon of gasoline, or using a MWh of electricity, and factor that into your calculations.

The fact that coal is the cheapest source of energy, but produces the most emissions, is a clear indicator to me that we have the financial model of energy & emissions backwards.  We’re not paying today for the pollution that we’re going to have to clean up tomorrow.

On the other hand, the worst possible day is hazy in the morning and sunny in the afternoon, and thats a fairly common weather pattern for us here in the Bay Area. Thats almost exactly what happened today, and we had our lowest output ever, at a measly 2.27kWh. Thats hardly enough electricity to power one TiVo for the day!

Thankfully, we’re approaching the winter solstice on December 21st, and that’s when the shadows start moving back in the other direction, giving us more and more energy. But, that also means that January will be just as bad as November, so it will be another 60 days or more until we see a significant increase in production.

This is exactly what we expected — the SolarCity installer originally predicted that in the month of December, we’ll only have 37% of our possible production due to shading. Thankfully, we’ve built up >$300 credit with PG&E, and now we can start to use up that credit.

I still expect us to be nearly “net $0″ for the year, but its looking less likely that we’ll be “net 0kWh” for the year.