Sunday, August 31, 2008

They made me do it

I'm trying to avoid political posts, I really am, but this is too much.

After spending months bashing Barack Obama as a neophyte with little experience in government and less experience in foreign policy, John McCain selected a running mate with even less experience in government and no foreign policy experience at all.

Except she's a woman. Chosen, the pundits say, in order to attract Hillary Clinton's core supporters. (Who are apparently expected to overlook her hardline conservative positions on social issues.)

This goes well beyond pandering; it's sexist and insulting. Clinton was a serious candidate. Palin is a token.

Tuesday, August 26, 2008

How to really support renewable energy

I was going to write a political post here. I decided against it: the election is generating enough sound and fury on all sides without my help.

Instead, I'll link to an especially sensible proposal on funding for the political football known as the Renewable Electricity Production Tax Credit. What about a tax on non-renewable electricity? An extra penny per kilowatt hour would add only a dollar or so to the average bill, but would more than cover the cost of extending the tax credit indefinitely.

Unfortunately, the idea that more expensive energy might actually be a good thing is likely to be too toxic for either party to touch, especially in an election year. Sigh...

Friday, August 15, 2008

The new power breakfast

If you get enough exercise, you can eat anything you want. According to the BBC, Olympic swimmer Michael Phelps consumes about 10,000 calories a day but maintains himself at only about 8% body fat.

The problem for us mortals is that "enough exercise" can add up to a pretty enormous commitment. Phelps spends five hours a day in the pool, and it's a safe bet that his workouts are a bit more demanding than your average recreational swim.

Tuesday, August 12, 2008

Watch what they do

NATO is a military alliance. Members explicitly agree that a military threat against one is a threat against all, demanding a collective response.

Clearly, NATO members are not interested in mounting a military response to Russia's invasion of Georgia. Yet equally clearly, that's exactly what NATO membership for Georgia would mean. (At least in theory.)

It's unfortunate that the Georgian people are the ones who have to experience the difference between words and actions.

Thursday, August 7, 2008

Making space

What's your job? Is it making stuff, or answering email? And how much time do you spend actually doing it?

Merlin Mann has a short series on the importance of making time for real work. It also explains why you may not get an email response from me right away.

Tuesday, August 5, 2008

All sunshine not created equal

Conversion efficiency, open circuit voltage, and other solar cell performance parameters are critically important to solar cell manufacturers and their customers. These parameters define the financial model for an installation, from the size of the array needed for a given output power to the installation's likely generation revenue. They set a viability threshold that new technologies must cross. Yet measuring them accurately turns out to be surprisingly challenging.

Though the whole point of solar energy is that the sun is readily available, the sun is a terrible light source for accurate measurements of solar cell parameters. Clouds, haze, and the time of day and time of year all cause deviations from the often-quoted 1000 W/sq. meter solar irradiance value, and from the "standard" solar spectrum. Instead, companies use solar simulators.

No solar simulator will precisely match the sun's spectrum, though, which means the cell being tested might respond differently in actual use conditions. Correcting for spectral mismatch is especially complicated for organic solar cells (as discussed in an article in April's IEEE Spectrum -- free for IEEE members), but several people have warned me not to trust non-certified reports for inorganic thin film cells, either.

With the solar industry's rapid growth, it was only a matter of time before someone stepped up to fill the need. VLSI Standards has introduced an NREL-traceable Solar Reference Cell, using a monocrystalline silicon cell for calibration of solar simulators. The company also offers calibration services for certification of customer reference cells. (This product is so new that it isn't on VLSI's site yet. Contact the company for more information.)