Hi Keith,
That is my place. Hydro pond is both spring fed and fed by a small seasonal brook, no pumping. I figure approximately 50% to55% efficiency for a high head micro-hydro turbine (Harris PM), not including, wire, batteries and inverter losses. I do not know the efficiency of larger turbines. Check with Canyon Industries (they advertise in Home Power). I've heard that they are significantly higher in efficiency (before transmission losses). I have heard that at least one larger scale hydro facility in NY State pumps back to the reservoir overnight at off peak rates, then releases generation water during peak rate periods. Also, Hydro Quebec buys off peak power from the U.S. grid when it's dirt cheap to power Montreal overnight. This saves some of their own water power for selling to the States during peak periods. A nice money making deal for Quebec. So, your idea is worth thinking about for regions such as Hawaii I believe. Dave From: [email protected] [mailto:[email protected]] On Behalf Of Keith Cronin Sent: Monday, August 24, 2009 2:43 PM To: RE-Wrenches Subject: [RE-wrenches] Solar and pumped hydro Hi Have any of you considered using PV to pump water to a holding area and releasing it and capturing the kinetic energy via a pelton wheel/hydro? If so, what do we think are the efficiencies and value of doing such a project are? Meaning, back of the napkin, PV is + - 77% efficient, minus "x" to pump the water to "x" elevation and the net result of the hydro = "____% efficient" It would be using the reservoir as the battery. There is approximately 300' of elevation from the PV system and water source to the reservoir area. I recall about 15 years ago, I visited a member on this lists Vermont home and he had a pond at the top of his property, but i don't recall how the source got to the reservoir? Might have been naturally fed? Anyway, the premise is, as grid access becomes more difficult to do, as the utility infrastructure gets saturated, what are our options for folks that want PV, but are limited in how much they are allowed to connect to the grid, without an interconnection study by a 3rd party to increase the comfort of the utility to have more non firm resources on their grid. We are seeing this happen here now and I was wondering if any of you have encountered this or are anticipating this in your areas? Any suggestions, calcs, recommendations, feedback would be appreciated. Keith
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