alt.energy.renewable

On Thu, 21 Feb 2008 13:54:48 -0800, "Rob Dekker"
wrote:

>
>"BobG" wrote in message news:4c507099-b117-4e8c-8127-e605468d05fa@v3g2000hsc.googlegroups.com...
>> Heard this on Paul Harvey driving to work today....
>> http://www.tucsoncitizen.com/daily/local/77596.php
>
>$1 billion solar-thermal plant near Gila Bend ....
>....At 280 megawatts, enough to power at least 70,000 households......
>
>That's about $3.60 / Watt installed.
>How does that compare to PV ?
>
>Rob
>
>

Its slightly better than PV, but not much.
Which begs the question why isnt it many times better.
Mirrors are more than 90% efficient at reflecting sunlight,
so why is the plants cost in terms of dollars per watt so poor.

The plant is going to cover 3 sq miles which equals 7.74 million sq
meters.
At 1000 watts per square meter the plant should make 7.7 GW if it
was 100% efficient, but its only going to make 280 MW which makes it
only 3% efficient.
Where is all the energy lost.