Posts: 8,471
Threads: 1,033
Joined: May 2003
The Dutch has used some innovative wind systems which might have value on a small scale in some locations here. Electricity storage has a high loss factor in battery storage. The Dutch use wind generators to run an air compressor to store compressed air in high pressure vessels.
Air pressure can be stored without loss. 100%. Then when needed the air generators can be run with compressed air.
The key here is acquiring a high pressure air tank. We have a heavy Navy presence on Oahu. Navy uses high pressure vessels a lot. It wouldn't surprise me if Navy surplus on Oahu didn't cut loose some of these from time to time real cheap. Compressors too. Who can use them? They are primarily uses by the Navy for submarines.
Just an idea.
In Holland they run some very large soccer stadiums with compressed air generation. It is all off the shelf technology.
Assume the best and ask questions.
Punaweb moderator
Posts: 3,188
Threads: 216
Joined: Sep 2007
regional electricity cost from the tesla motor club
interesting read - euro's being worth about 1.20 - $1.30
http://www.teslamotorsclub.com/showthrea...world-wide
Posts: 526
Threads: 11
Joined: Oct 2006
"something is missing - common sense would dictate pumping during the day and using the energy from stored water at night."
As is typical, power usage at night is relatively low, less HVAC, lighter machinery usage etc. They don't need extra power supply at night. Why they don't reduce usage of their soft coal plants during the day in favor of the pumped storage I don't know.
Posts: 526
Threads: 11
Joined: Oct 2006
"The Dutch use wind generators to run an air compressor to store compressed air in high pressure vessels."
Easy to imagine a small Puna scale apparatus with a DC compressor on one end feeding an air tank and run by some set of solar panels. The compressor and tank could be sized, say, to fill to capacity at full rated pressure on eight hours of sun (or a couple of days partly sunny). Then, perhaps on a timer, the air is released on the other end of the air tank through a DC generator that is hooked into the normal solar panel input through a charge controller. The generator would create a fairly constant 12, 24 or 48 volts. There's probably some engineering solution to maintaining a constant voltage with decreasing air pressure and varying load.
The idea is that the DC generator would simulate the solar panels at night reducing the discharge of the battery bank. As the air runs out the batteries would automatically take over. Probably cost a few thousand dollars, but your batteries, the weakest link in a solar system, would likely stay at a higher state of charge, therefore be much longer lived. But don't know if it's actually practical.
Posts: 3,188
Threads: 216
Joined: Sep 2007
or catching water in a basin at altitude on this side and sending it to Kona in a pipe - with a few turbines inline along the way
Posts: 2,490
Threads: 222
Joined: Dec 2005
Well, air pumps are all fine and dandy that is till you look around and try to buy a air powered generator. Ever try to find one? No? Well, that because they don't exist yet. But I'd imagine if you could find one you could probably buy 5-10 20 gallon air tanks to power a 2500 watt generator for 12-16 hours depending on load.
Altho, I highly doubt america / hawaii gives a flying F about conserving oil/power ... If we did we would get rid of all these gas guzzlers off the streets. Granted my car get's 40 MPG. I'd love to go solar but still trying to figure out for me how I can buy a 2K watt system for under 8K bucks that can be reliable. Not just some cheap Chinese inverter that burns up in the middle of the night and all the food in the fidge spoils... JOY...
Posts: 771
Threads: 37
Joined: Feb 2006
According to the WSJ ed page Germany is an economic powerhouse ascribed to electricity subsidies to exporters like Volkswagon and BMW. I must have had the WSJ koolaid- if EU didn't have alt energy mandates Germany wouldn't need electricity subsidies??
Posts: 2,466
Threads: 316
Joined: May 2008
"... But I'd imagine if you could find one you could probably buy 5-10 20 gallon air tanks to power a 2500 watt generator for 12-16 hours depending on load. ..."
Make that about 5 to 10 MINUTES and that's using a 20 gallong tank.
Puna: Our roosters crow first
Posts: 3,188
Threads: 216
Joined: Sep 2007
depends on how many atmospheres you pump up the tanks to
ultra high pressures require frequent tank inspections
Posts: 14,122
Threads: 424
Joined: Aug 2012
...at which point you're right back into the license-permit-inspection scam.
