Awesome! Now the race is really on. When will silicon PV get to 25%?

Thin film is suppose to be a lot cheaper. I just hope there as durable as the old ones. Mine are 15 years old a still going strong.

What are the efficiency rates of coal? I saw a ZDnet article talking about how a large-scale coal plant puts out 500 megawatts per year, comparing it to the manufacturing capacity of the plant and the energy that can be generated with the solar panels produced through a year... but I would also like to see metrics about the efficiency rates... to put it into context even more.

liveinvt, I'm not sure I see the link between solar panel efficiency and coal plant efficiency. Could you elaborate a bit more?

I just want $1/watt solar cells already!

Coal I don't know. But the best internal combustion engine rarely breaks 50% efficiency. Diesels are a little more at around 60-75% efficient. But remember, the laws of thermodynamics prevent anything from being 100% efficient.

Remember that current power plants are nothing more than steam engines driving turbines turning generators.

If someone does know the efficiency of the coal plants, I would like to know the efficiency of energy input to energy removed at my wall plug. This includes processes for ground extraction, to transport, to burning, to steam, to rotary motion, to power grid and system parasitics, to light bulb efficiency.

I'm more interested in when will I be able to buy it.

Dumb question, but can someone help me? The post refers to a high of 20.3 % efficiency without concentrators, so when the light is concentrated the efficiency does go up? By how much, and when does silicon get too hot that it loses some of its efficiency? I only ask this because I smell a weekend DIY project coming up.

Thanks.

- from various wikipedia articles

None of these numbers count fuel to mine, process, deliver or dispose of waste which can be alot with coal and nuke.

>95% best production electric motors
>85% common lead acid car battery
>95% best batteries
>99% production capacitors

>90% best production gas turbines with cogeneration (hot water/heating side effect)

>92% US electric grid
>96% US natural gas network

So we can see that the best fossil solution is natural gas pipeline to the house to run a co-generation system. Such systems are already sold in Japan and can reach over 90% if you need the heat for water or house heating.

We can also see that even with a coal fired plant, wired delivery, charging the batteries, an electric car is still better than a gas car and that's before we even consider regenerative braking and how much longer electric motors last.

Coal and nuke people love to talk about upfront costs of their powerplants. They never want to talk about fuel costs, waste disposal costs or polution. When you look at total lifecycle costs, solar and wind win hands down.

The real impediment to implementation is the entrenched oil and coal interests get all kinds of tax benefits and subsidies both for themselves and for their users. A coal plant converts hundreds of tons of coal to polution every year yet instead of getting a bill for the dammage they do, they are allowed to deduct the cost of the coal from their profits on their taxes.

Anyway, NanoSolar thin film costs less per watt than an empty coal plant does to build - before you even buy any coal. Now, today, it's shipping. Their entire production is already sold though 2009. There is no reason to build another coal plant, only more solar.

Coal plants are measured in Heat Rate, a measurement of the efficiency of converting coal into electricity. It's not the same as a percentage, http://www.econsci.com/euar9801.html, but can be converted to such.

Most modern coal plants hover between 9000-12000 There's a paper here: http://www.econsci.com/euar9801.html. The higher the heat rate, the worst the efficiency. The curve of efficiency on a boiler is basically a shallow bowl, with the sweet spot near the maximum delivery.

This fellow says the rough percentage of all this is 42% for a coal plant in terms of efficiency. http://www.eng-tips.com/viewthread.cfm?qid=179562&page=1

Efficiency of coal versus solar is irrelevant.
Coal may be more efficient but it is a finite resource that is very polluting.
Solar is a limitless resource with very little environmental impact.
Cost per watt along with environmental effects thrown in should be the real measure.
How you measure the environmental effects is the hard part.

% efficiency matters less than $/watt in most applications.

Most of us would run out of money before running out of south facing roof space, and even if we did pole mount or tracking pole mounts are an option.

A typical coal fired plant's-
Thermal Efficiency: 33%
Fuel->Electricity: ~27%

In order to properly compare the efficiency of a CFP to a PV module all steps in the energy chain must be accounted for. Mind you that there is a loss at every step.

Coal Fired Plant-
Sun->Biomass->Coal->Mining->Transport->Firing->Generator->Grid

Photovoltaic-
Sun->Grid

See the elegance of PV? Simple.

Whoever said diesel could reach 60-70%TE.... wrong, sorry. Two stroke diesel engines struggle to crack 50%TE. State of the art LDV deisels hover around 42%TE. Otto cycle engines manage 30%TE while Brayton cycle engines can manage 65%TE.

Don't forget, that's TE (Thermal Efficiency) and completely disregards mechanical losses (such as piston, cam, valve, or transmission friction). It has been estimated that, on average, less than 10% of the energy stored in the fuel tank of a gasoline powered car actually makes it to the wheels. I've seen estimates as low as 1% but I find that too extreme.

Way to show off your American't side there folks. I would like to see a comment page from other countries and then look at this page,.......blah,blah[excuse],bla[cry/whine], blah, blah [ change the subject to allow me to waste], Blah, Blah! [leave my energy consumption alone] whawaahn. What pathetic county spirit.
How about "Where can I buy one and when are they going to be avail for install? What kind of production and manufacturing is needed? Can American companies make these? Can I start a manh=ufacturing plant in my town??

yes now we have lighter for roofs for homes and cars ,and toys,,whats next

Does it really matter how much E a solar plant uses, if we are reducing the amount of E consumed by fossil fuels overall? If more people switch to solar panels, less will need the E generated by the coal plants right? If the solar panels themselves can compensate for the amount of E saved overall, then what is the issue?

I'm more interested in $/W than efficiency.

Who cares if you can get 0.5% more efficiency if it costs even 0.6% more?

copper indium gallium diselenide ....
mmm I wonder how much of that there is around?
There is also the possibility that in 20 years from now we just happen to find that it's all over our rooftops and its bad for our health. And the costs for disposal when it has reach its lifespan? (remember asbestos)

Disposal cost of solar devices couldn't be near as much as the cost of the toxic stuff that comes out of a coal fired power plant.
Mercury, Arsenic, Sulphuric Acid, Lead, never mind the CO2. All in millions of tons a year