Pumped Hydroelectric Storage

From Open Source Ecology
Jump to: navigation, search

Calling the engineers in the audience - I just ran through some calculations on the feasibility of water pumping storage at Factor e Farm, our facility. The numbers look really good on paper. The drawing shows two quarter acre ponds - the contour lines are at 1 foot elevation intervals, so 30 foot drop between the ponds. The calculation yields 24kWhr of energy storage from this using proven microhydro technology - where the elevated pond serves as a reserve that can be pumped during daylight for gravity water storage. This is an open call for review of the calculations, see below.

Explanation:

Can we consider a storage hydro system that pumps during the day and generates electricity by night? Quick calculations: 1/4 acre pond, 6 foot deep. That is about 2000 cubic meters of water. Take another pond 10 m lower. The energy of water going from pond 1 to pond 2 (see drawing attached) is MgH = energy = [2000 cu m]x[1000kg/cu m]x[10 m/s^2]x[10 m] = 200 MJ 200 MJ = 200 MW for 1 second, or 200 kW for 1000 seconds, or 2 kW for 100,000 seconds - but assume 50% system efficiency (85% pumping, 85% generating, then 20% friction loss)

THAT IS over 24 HOURS OF 1KW OF POWER!!!!!!!!!!!!

Cost will be $1.5k in 4" pipe (about 1000 ft), $1k in power equipment, $10k in excavation + trenching for 2 ponds. If we have our own dozer, that will be $3k system cost. $3k for 24kWhr of power storage appears to beat batteries by a factor of 5-10 in cost. Sure looks good on paper. Are these numbers sound?

If this works, we will consider this project for a future workshop in permaculture and open source technology, like the ones we're running now (http://bit.ly/1lHE2fw). If anyone can help us develop this project, please let me know.

Phs.jpg

References

Turbine Sources

Contacts

Contacted Regrarians, Permies, TED Fellows on Facebook.

Hi Permies, I've been bouncing this pumped hydroelectric storage idea, which we are considering for a future workshop. This appears feasible at our site, with 30 feet of head, using two quarter acre ponds. I'm contacting http://www.canyonhydro.com/micro/microfaq.html#FAQ_HowMuchPwr to find out more about Pelton turbines - any ideas on other reputable Pelton turbine sources?

Calling the engineers in the audience - I just ran through some calculations on the feasibility of water pumping storage at Factor e Farm, our facility. The numbers look really good on paper. The drawing shows two quarter acre ponds - the contour lines are at 1 foot elevation intervals, so 30 foot drop between the ponds. The calculation yields 24kWhr of energy storage from this using proven microhydro technology - where the elevated pond serves as a reserve that can be pumped during daylight for gravity water storage. This is an open call for review of the calculations, see below. Explanation: Can we consider a storage hydro system that pumps during the day and generates electricity by night? Quick calculations: 1/4 acre pond, 6 foot deep. That is about 2000 cubic meters of water. Take another pond 10 m lower. The energy of water going from pond 1 to pond 2 (see drawing attached) is MgH = energy = [2000 cu m]x[1000kg/cu m]x[10 m/s^2]x[10 m] = 200 MJ 200 MJ = 200 MW for 1 second, or 200 kW for 1000 seconds, or 2 kW for 100,000 seconds - but assume 50% system efficiency (85% pumping, 85% generating, then 20% friction loss) THAT IS over 24 HOURS OF 1KW OF POWER!!!!!!!!!!!! Cost will be $1.5k in 4" pipe (about 1000 ft), $1k in power equipment, $10k in excavation + trenching for 2 ponds. If we have our own dozer, that will be $3k system cost. $3k for 24kWhr of power storage appears to beat batteries by a factor of 5-10 in cost. Sure looks good on paper. Are these numbers sound? If this works, we will consider this project for a future workshop in permaculture and open source technology, like the ones we're running now (http://bit.ly/1lHE2fw). If anyone can help us develop this project, please let me know.

Other Types of Gravity Storage

Links

  • Alexander Slocum, MIT - ocean windmill storage - [6]
  • other OSE Wiki pages: Pelton Wheel
  • Flow battery - the cheapest form of chemical storage possible - $1/kwhr for materials, and $10/kwhr for balance of system