Posted by Max Dunn Tue, 29 Apr 2008 17:49:49 GMT | no comments
Wind power can now produce energy as cheaply as coal, about 5c per kilowatt hour (kWh). Solar power is almost to the point where it can produce energy at the marginal electrical rate of about 10c kWh. So with oil prices over $100 barrel, natural gas prices doubling, and all the concern about CO2 and other noxious emissions from coal plants, why aren’t more wind and solar projects being built?
Posted by Max Dunn Tue, 29 Apr 2008 17:18:39 GMT | no comments
Last night I attended a seminar put on by the Going Green! meetup group and the speaker was Craig Lewis who is VP Government Relations with GreenVolts. GreenVolt’s goal is to “deliver power to utility companies at fossil fuel costs”.
Craig talked a little about the GreenVolts product, which is a concentrating solar collector system with advanced tracking and is designed to be interconnected at the 12kv distribution level in sizes ranging from 1 to 20 mega-watts (MW). However, his main topic was “Accelerating the Transition to Smart Energy.” His conclusion was that to make alternative energy sources take off, the government needs to shift the subsidies paid to oil companies into long-term feed-in tariffs, i.e. requiring the electric companies to buy power at a set price for the next 10 to 15 years. This would allow alternative energy projects to have a guaranteed return and thus enable them to get long-term financing.
While Craig wouldn’t divulge the cost of their system, he did say it was about half of a typical flat-panel installation, so I am guessing that the cost is about $4 per watt, which would mean they could produce power at less than 9.5c per kilowatt, which is the rate they would be selling it to the utilities.
He also threw out some other interesting numbers:Here are the complete notes:
Posted by Max Dunn Thu, 24 Apr 2008 04:38:48 GMT | 4 comments
How much would it cost to build a solar nation? Here are some interesting numbers:
The IEA estimates that it will take a worldwide investment of $5.4 trillion dollars in oil exploration and development in order to meet the demand for oil in 2030, if oil usage continues to grow at its current rate. Since the U.S. uses about 25% of the worlds oil, our cost would be about $1.35 trillion.
Scientific American estimates that if we provide less than a third of this amount as a subsidy – $420 billion – then we can build a solar collection, storage and distribution system that would provide 69% of America’s electricity and 35% of it’s total energy by 2050.
So, can anyone say that building a solar nation is too expensive?
Posted by Max Dunn Thu, 24 Apr 2008 01:08:48 GMT | no comments
Today I went to an interesting Energy Seminar at Stanford. The speaker was Scott Elrod who works for Parc and studied Applied Physics at Stanford. He was talking about a product they are working on called the SolFocus which is a concentrating solar collector and their hope is to get this down to $1/watt. Here are the notes from the talk:
Posted by Max Dunn Sat, 12 Apr 2008 20:33:12 GMT | 1 comment
A new $3.2 million hydrogen fueling station opened in Sacramento last week that has 80kW of solar PV panels are used to produce the hydrogen, so it won’t use any outside energy. Let’s take a look at how efficient this is:
SOLAR OUTPUT:Considering the solar array probably cost probably cost around $10/watt, or $800,000 out of $3,200,000, the hydrogen “refueling station” cost approximately $2,400,000.
If that money had been used to build $2,400,000 of solar installation plus $800,000 of EV chargers – about 240 kW of solar and 160 EV charger stations – enough for well over a million miles per year (80 cars worth) instead of just a hundred thousand hydrogen fuel-cell vehicle miles (8 cars worth). So the hydrogen fueling station is only 10% as efficient as building solar recharging stations for battery electric vehicles.
(From RAV4-EV Digest, Vol 58, Issue 12, comment by William Korthof of EESolar)
Posted by Max Dunn Wed, 06 Feb 2008 02:15:27 GMT | 4 comments
Regardless of what Bush thinks, hydrogen powered vehicles are not a viable alternative.
First off, hydrogen is not something that can be “mined”, but instead must be produced using other energy sources [1]. With current technologies, electricity from hydrogen fuel cells is four times more expensive than electricity from the grid [2]. Secondly, hydrogen is very difficult to ship and store. Leave a hydrogen car at the airport for two weeks and half of the fuel will be lost due to evaporation [2]. Thirdly, while hydrogen fuel cells are clean, currently hydrogen fuel cells are costly to produce and fragile [3] and only about 50% efficient [4]. Lastly, hydrogen is not very dense so cars would need to have a tank 2-3 times larger than their gasoline tanks [3].
With all things considered, it doesn’t make sense to power cars with hydrogen; instead, just put batteries in the car and use the electricity directly.
References:
Posted by Max Dunn Wed, 23 Jan 2008 18:33:26 GMT | 8 comments
I don’t have a lot of confidence in PG&E. It seems that every time we have a big storm, our power goes out. Once, it took 3 days for them to get the power back on! So I have been considering installing a battery backup system for my house to get through these power outages.
If I install a battery backup system, I was wondering if it would be profitable to charge up the batteries at night when electricity costs are low, at $0.05/kWh, and then use it during the day when electricity costs are high, at $0.11/kWh to $0.29/kWh [9]?
Posted by Max Dunn Wed, 23 Jan 2008 01:31:31 GMT | no comments
It seems awfully strange that a company that sells power would subsidize compact fluorescent lights (CFLs) that use less energy, and give rebates for energy efficient appliances. This would be like Starbucks giving awards to people who cut down on their coffee drinking! But even though this seems strange, power companies trying to cut power consumption actually makes sense.
Posted by Max Dunn Tue, 22 Jan 2008 22:57:16 GMT | 8 comments
Nowadays, if you are looking to install a hot tub, your only option is likely to be a hot tub that heats with electricity. The salesman will tell you that they are very well insulated (which they are) and that it will only cost about $30 per month of electricity to heat it (which is possible but optimistic.) Let’s look at the math and physics behind this.
Posted by Max Dunn Mon, 07 Jan 2008 17:01:10 GMT | 1 comment
We like to think that we live in an advanced society where the miracles of technology provide a high quality-of-life. However, the recent storm in California proved what a primitive electrical distribution system we have.
This storm was nothing special; it didn’t have hurricane power winds or particularly spectacular lightning. It was just a run-of-the-mill winter storm that we expect every year or two. Yet it was able to knock out electric power for more than 1.6 million people, of which 420,000 people still didn’t have power after a few days.
It is not hard to see why our power system is so antiquated – just look up in any neighborhood. There you will see power lines strung on poles, the same as they were a hundred years ago. This system is very fragile and will continue to break down in high winds and lightning strikes. We do have a better solution – bury the electrical cables underground, which will make them impervious to these common elements of nature. But we live in a fairly backwards country where we would rather suffer through losses of power every year and frantically send out crews to fix problems after they occur rather than spend the money to solve the problem once and for all.