Solar Systems making the sun work after dark (hydrogen as power storage)

[OKIsItJustMe]

http://www.news.com.au/heraldsun/story/0,21985,22800151-664,00.html

Solar Systems making the sun work after dark

Olga Galacho

November 22, 2007 12:00am

RENEWABLE energy company Solar Systems says it has developed a way of converting solar power into electricity around the clock, even when the sun is not shining.

Managing director Dave Holland told BusinessDaily that although the process, which produces hydrogen and stores it, is still years from connecting to the electricity grid, it has been demonstrated to produce baseload power.

He said less than 1 per cent of the planet's arid lands could produce the entire world's energy needs using the technology, without harmful emissions, concern about finite fuel supply, or toxic waste.

...

Solar Systems has begun building a research and development plant on a 31ha site at Bridgewater, near Bendigo, to commercially demonstrate its hydrogen-solar technology.

...

The technology that will continue to produce electricity when the sun goes down works by using the concentrated solar energy to separate water into hydrogen and oxygen through a spectrum splitter and then an electrolyser.

The hydrogen is then stored in large onsite tanks, ready to be used by fuel cells for electricity generation at night.

Nothing terribly new here. Naturally, the same method can be used with wind power.

[lovuian]

1. Lets do it

See we can do it

[Xipe Totec]

2. Question

so they build this on arid lands and store enrgy by splitting water, which they get from...

... where?

[kestrel91316]

3. They can use some of their on-site electrical power to run

a dehumidifier-type thing to pull water right out of thin air.

I know. I must be smoking crack.

[OKIsItJustMe]

4. Think about it. If you do it right, it's a closed water cycle.

Today, I take X molecules of H₂O, and split it to produce X molecules of H₂ and X/2 molecules of O₂.

Tonight, I take my X molecules of H₂ and combine then with X/2 molecules of O₂ to produce X molecules of H₂O, electricity and waste heat.

Now, that H₂O will be in the form of water vapor, which I could simply vent; but what do they do with it in space, where water is also in short supply? Why, they condense it, and drink it of course. (Even the waste heat is used.)

http://spaceflight.nasa.gov/shuttle/reference/shutref/orbiter/eps/pwrplants.html

However, what I'll do is save it for reuse tomorrow.

[tinrobot]

5. A lot of the water can be recycled

Hydrogen generators usually emit water as exhaust. So, basically, you burn the hydrogen at night, then convert the water exhaust back to hydrogen during the day.

Might not be a completely closed system, but it would be close.

[jpak]

6. When you reform hydrogen to produce electricity - you produce water

Very pure water - it's a closed system that recycles all the water it uses...

[Xipe Totec]

7. That's technically true

the water can be recycled in a closed system.

We just need to make sure that it actually is recycled.

Because, energy-wise, it is cheaper to vent the water than it is to recover it.

[eppur_se_muova]

8. This is the best use of H2 -- energy storage, not transport'n fuel. nt

[TheWraith]

9. Electrolysis is an incredibly lossy method of storage.

You lose 30 to 50% of the power you put into it. Not to mention the fact that a hydrogen generator would also be lossy. Net result, you need probably 3-5 times as much raw capacity as you actually need for energy. Not good.

He's also being incredibly optimistic with that 1% figure.