Is building a home water battery worth it?

I have been kicking this idea around for awhile now and I am hitting a wall with it and I figured I would tap into the expertise on this forum.  On our property we have a 2 acre pond about 300 feet down an embankment from out house, beside a river.  The regulations in Ontario make it extremely difficult to use the river to produce hydro power.  The river has a high flow rate but not much head.  I have yet to find a run of river system that is available to purchase.  Lots of interesting prototypes out there but I digress. I have been playing with solar panels as of late and I am in the design phase of a pond aeration system and I got thinking I could use solar to pump water up the hill, fill a pile of those 1000 litre water cubes then let the water run out when the sun was not out to make power?

Any thoughts and input welcome.  This may just end up in the pile of other energy producing ideas I have tinkered with over the years and come to nothing.

Thank you for your time and consideration.

Regards
Brayden

You could, but once you account for the cost of materials (pump, tubing, turbine, generator, fittings, electrickery like inverters and charge controllers) plus your time hooking everything up and dialing it in, even if you can score a bunch of IBC totes for free this setup will have a hard time competing with plain old battery storage.

Not saying you shouldn't try it, especially if you have a decent hill. But it's one of those technologies like wind...works really well at big utility scale and not all that great at a homestead level.

Thanks Phil.  I figured as much.  I may still tinker with it.

Don't know if you saw this thread, but the second video is a good example of someone who's done micro hydro very well. Note how big his tubing is to minimise friction loss. You'd want to emulate that for the generation side of things. The pumped inflow could be smaller and basically flow whenever you have excess power. You'd need some sort of weir and debris trap like he has to protect your pump and turbine from all the floaty and gritty things in the river.

I noted in that video that he was generating about 400 watts of power continuously with his rig, and he talked about 1-2 litres per second going into the pipe. That means that with a volume of well over 100 IBC totes worth of water he's getting less than 10 kWh of energy per day. Don't know what his static head is but we could derive that from what we do know.

If you do mess around with it, there are lots of us who'd love to see the journey.

I was curious about gravity storage too - pumped hydro is essentially the safest form, and the easiest to scale up. However, it has inherently low energy density. Some numbers:

potential energy = Mass(kg) * Head (m) * Acceleration of gravity (9.8m/s^2) and gives you a number in Joules. 3,600,000J is equal to 1 kwh. You will also need to figure in losses due to friction in your pipe, your turbine, your generator, your wiring, your batteries, so lets say half of it is available to actually do work.

The most generous possible reading of your situation would be that you have 100 meters of head, but i am guessing the creek is actually just 300 feet away, and not 300 feet lower. Even with 100m, 1000kg of water would store 100,000J, or .028kwh. Since we only get half back, lets call it about 15wh. To put that in perspective, that is about as much power as 5 AA batteries. If you only have 10 meters of head, well, you are going to need a lot of water :)

The only way this works is to make the system very big. Build a giant pond up a giant hill and run a giant very efficient turbine being fed with a giant pipe. You will also need a giant pump, and it wouldnt hurt to have some nuclear power that has extra energy at night and cant be shut down.

Still, it is a fun idea, and if you are interested in that sort of thing, read about some of the different "gravity batteries" people have dreamed up. Pretty cool.

I am thinking about trying it come spring. I got two places to put 1 acre ponds with a height difference of fifty feet. I have to run the numbers but  I know hydro.

My employer does pumped storage and makes it work without nuclear power so maybe I can at home???

It would be nice to show micro pumped storage could work.

Solar Array 33kW @ $20,000 (100kWHr/day)
Pump/MicroHydro+ Pipe 33kW @ $33,000 (50kWHr/day with 50% efficiency)
MicroHydro/Pump + Pipe 33kW (with 50% efficiency 25kWHr/day net output)
Pond Stored Energy =  480kWhr * 50% efficiency = 240kWHr (3,000,000gal, 50ft head) @ $5,000+

With the pond as a battery you dont have to buy a new battery every 3-10yrs, and the 240kWHr could last 3days to 10days if it is overcast. The pump/micro-hydro acts like a charger/inveter, overall I think it is a good project. The pond can also power a Heat Pump too, and maybe grow some fish

Pond = 3,000,000gallons at 10ft deep, 1acre
Flow = Gallons in pond / Minutes in a Day = 3,000,000 / 1440 = 2,000gpm
Net power output = 1/5 * Flow * Head * Efficiency = 1/5  * 2,000gpm * 50ft  * 50% Efficiency = 10kW or 240kWHr per day.
Stored Energy = 240kWHr / 50% Efficiency = 480kWHr

There are other ways to use this mechanical energy than electrical generation, and they are probably more efficient. Think about on-demand uses: directly driving power tools or grain mills, generating compressed air, pumping water to other locations.

Pumped storage has really come into its own now that solar has really taken off.

I know commercially it is a huge money-maker because solar has caused the morning ramp and peak demand to really rise in price, destabilizing the market price of electricity. That makes pumped storage really valuable.

It could be for retail customers too, as the differential becomes more extreme. The greater that is, the more economical viable the project becomes.

I know at work they are now making two cycles per day, which is really lucrative as it used to be only one. Add in green credits and it makes sense. For landowners, all this comes into play as well. Just be careful and build it right; the emergency spillway should dump twice as many gallons per minute as what can be pumped for safety sake.