Solving the worlds energy crisis - 1 step at a time...

[TassieTiger]

So some may know that I’ve been messing about with solar power for heating and recently I sorted a solar water pump to a header tank...and it go me thinking.
Do this is just a kick around idea but bare with me.

Those that have solar on their house will know that - the panels generate far more power than you can use during the day, resulting in a surplus of power that is sold back k to grid for bugger all.
Ideally, that excess power would remain on site so you could use it at night - and this can be achieved via batteries but they are extremely expensive and need maintenance and room and replacing. But - at the moment, they are the best we have for storing energy...except - my header tank gave me an idea.

What if we could use that excess solar energy to store “energy” via a different form? Instead of storing it as electrical energy, we stored it as mechanical ?

To the crux of my idea;
During the day, excess solar electric energy drives a 12v water pump that pumps water to a sizeable water tank on a stand - until full. At night - the mechanical energy storage - water is released via a gate valve, that allows cascading water to tumble and turn a generator that produces power to run heater, lights, etc at night. The gate valve can open more, if additional energy is required or turned off if no ones home...the water would be collected at another water tank below ground-then as the sun rises, the excess solar power again starts the dc water pump to return the ground tank water to header tank. A closed loop, self sustaining, off grid system.
Heights, plumbing, gate size, panels, pump, inverter - generator and impeller - all need to be calculated and I think at least some battery power would be needed for monitoring, etc.
What do you think - feasible ??

[eddievic]

In two words
Friction
Inefficiency

Wont work that well. Just store it in a couple of truck batteries with an inverter

[Larry]

This is done in several parts in Europe like Germany where they have some very high mountain lakes. They also use Hydro electric systems a lot on thier mountain rivers and streams. Even in some very small ones and small turbines for local city use. They will pump the water from a bottom lake to a mountain lake and then drain it to produce electricity when needed.

[mchughcb]

10B later and you'd have snow hydro V2.

I've been to this place with the missus and I have to say it is impressive. https://en.wikipedia.org/wiki/Cruachan_Power_Station

[Ziege]

There are mechanical storage systems in place around the world, However they have a lot of diminishing returns and only tend to work in a large capacity situation, the inertial and drag coefficients of a lot of the kit required to store the water and then in return generate power from it, tend to use more putting it in than it returns coming back out. thermal soaks work also but these also have a lot of issues and vulnerabilities the number one issue in both is that thermal energy is a byproduct of inertial/kinetic energy this thermal energy in a mechanical setting is considered loss and is parasitic to the gains sought as an end result, so basically if you quantify the amount of potential energy that can be made, that total will have to then be divided into what is lost through mechanical drag and other inefficiencies what often ends up being the case is that the return of usable energy is often quite low, so whilst I could confidently say that you should be able to power maybe your lights and some phone chargers off of the tank as it recirculates down I am not confident you would see the same available energy to run higher wattage/amperage devices like microwaves, vacuum cleaners, fridges, dryers or anything off it, because unlike a battery that energy is not actually sitting there 100% ready to be used/dissipated so trying to draw more current than what a small generator on a water turbine would be creating wouldn't be an option. but yes this kind of storage goes back millennia, there are mechanically stored water powered types of plant/devices that have been used all throughout history, however most were manually filled by someone with a bucket lol. Ive kept it as layman as I can, its too long since I did physics at school/college to confidently go into more detail without having to basically give myself a refresher course so I hope that makes sense.

[eddievic]

Very well explained zeige

[TassieTiger]

There are mechanical storage systems in place around the world, However they have a lot of diminishing returns and only tend to work in a large capacity situation, the inertial and drag coefficients of a lot of the kit required to store the water and then in return generate power from it, tend to use more putting it in than it returns coming back out. thermal soaks work also but these also have a lot of issues and vulnerabilities the number one issue in both is that thermal energy is a byproduct of inertial/kinetic energy this thermal energy in a mechanical setting is considered loss and is parasitic to the gains sought as an end result, so basically if you quantify the amount of potential energy that can be made, that total will have to then be divided into what is lost through mechanical drag and other inefficiencies what often ends up being the case is that the return of usable energy is often quite low, so whilst I could confidently say that you should be able to power maybe your lights and some phone chargers off of the tank as it recirculates down I am not confident you would see the same available energy to run higher wattage/amperage devices like microwaves, vacuum cleaners, fridges, dryers or anything off it, because unlike a battery that energy is not actually sitting there 100% ready to be used/dissipated so trying to draw more current than what a small generator on a water turbine would be creating wouldn't be an option. but yes this kind of storage goes back millennia, there are mechanically stored water powered types of plant/devices that have been used all throughout history, however most were manually filled by someone with a bucket lol. Ive kept it as layman as I can, its too long since I did physics at school/college to confidently go into more detail without having to basically give myself a refresher course so I hope that makes sense.

Agreed.
But losses can be accounted for.
There are modern and efficient water impellers on gensets lined with multi windings on Ti bearings - these things spin for ages from a finger push, very little drag and make decent power. I’ve not researched latest tech - hopefully it’s improved
I’ve witnessed a cannabalised wind turbine, placed at the bottom of a 2.5m x 100mm pipe - generating 550w of power - running a heating element in a still...from the water feeding down to it. I suspect a more purpose built unit, (smaller blades, maybe set into the pipe rather than enclosed) would be more efficient. A motorcycle gen might be an option...

The thing to consider - regardless of losses - is the solar panels in 6-12kw array, more often than not, produce excess power that is wasted anyway, so any real return is a win.
100% agree - you’d not be able to run large / hard hitting AC devices from a water wheel generator device - but you could run them for short periods, off an inverted battery dedicated for that purpose. So maybe, a water reticulation system as suggested could form a “part” of a storage system...

[eddievic]

Hmm 100mm pipe diameter would empty a 1000L header tank within minutes just on gravity alone. Anymore than a couple of thousand litre tank and tbh you will end up spending more on strengthening the footings and the frame than a tesla powerwall. If you are on a hill you might be alright with a 100k litre tank. Probably last the night.

And anyone running a generator knows the more things you turn on the more fuel it consumes, that's because it takes more energy to spin the dynamo. So you will need more kinetic energy from your header tank

As zeige said its only viable on very large systems.

But why not do it

[eddievic]

Actually i did some rough calculations.... (i could be wrong)

But i come up with 97 litres of water flow per second from a 100mm pipe. By putting an impeller in the way the flow rate will slow down. So even at half flow that 100k litre tank is not going to last 1hr of use.

[TassieTiger]

Of course a 100mm pipe is too big, and why would a gate valve be incorporated other than to stem flow rate? ...I’d expect with streamlined design a 1 inch poly could be utilised and still regulate flow to ensure maximum generator efficiency is realise.

Tesla power walls are great for a couple years (costs are extreme though) and then efficiencies drop off dramatically...snd then need full house replacing. And youve still got the surplus solar energy being bled off for nought.

[Blr243]

I only read the first post. I really like the idea. Weather it works or not rermains to be seen but nobody ever got anywhere without thinking of new ideas to solve problems .....the world And all itS problems needs lots of thinkers

[Blr243]

I think some of the water needs to be semi accessible so birds can bath in it too .......and it would bee nice to hear the water fall , from a personal therapy , rerlaxation point of view

[TassieTiger]

I think some of the water needs to be semi accessible so birds can bath in it too .......and it would bee nice to hear the water fall , from a personal therapy , rerlaxation point of view

Ironically BLR - this could potentially work with an 2m old school water wheel...as the extra radius would allow for additional windings...but water volume would be the issue...
But imagine that - coming home from work - turning the button on to activate water flow and then listening to water fall all night whilst it generates your power...bliss.

It’s just an idea - it’s far from “clean”. If a renewable energy development co wants to donate dollars to test, I’d happily undertake. There are plenty of hurdles to overcome - some of which are in “test phase” on you tube - ie a gent on there 3D printed a number of tiny water impellers that fit in his down pipes...etc. Etc.

[marksman]

a dairy farmer l know has been toying with this idea for a while now,
he was telling me that for parts of the year he milks in darkness so his solar panels are useless to him,
he said that if the water was sent up his hill during daylight the solar panels would cover that and the turbine would cover the electricity he would use milking in the dark
he also spoke about the efficiencies of the new turbines although its more than l can digest l reckon its a perler of an idea

[TassieTiger]

Cheers MM. A lot of ppl are using creeks out the back of their properties to run old washing machine drums and things like that... it it’s hard to regulate the flow as it’s based on water coming from the sky.
In fact - one of the better whiskey destillers in this stste, Pete Bignell of Belgrove - powers his distillery from junk he has turned into power generation - it’s quite unbelievable to witness what he’s made...wind turbines from old plastic petrol containers that had holes in them, windows turned into solar frames, heaters from mirrors, etc etc - but his main power source is from his seasonal river - a hydro set up. I might run my idea bY him...he has enough money to do something with it if he thinks it has merit.

[Ziege]

I think you will run into too greater losses kw/torque wise, these direct mechanical losses are inalienable as you need some sort of "resistance" to induce a current.

Example, -
the alternator on your car makes energy in gross excess to the electrical needs of your vehicle, the amount of watts per energy at set amperage is way more than you would need, however the fuel source is not used efficiently by either the engine or the alternator, and the heat and other energy losses due to mechanical drag and friction are completely negligible because the exercise is making power, not looking for a certain yield of efficiency, likewise alternators HP/Kw scavenging isn't really factored into the overall energy/fuel consumption due to the necessity of its being there and the fraction of a percent difference it makes vs the losses of efficiency from the drive train and engine itself far outweigh it...

this is the inverse of your hypothetical situation, you would be looking to have as much efficiency vs output of your generator/alternator to yield the greatest return from your finite storage. however there is the inevitability that you will have multiple points of resistance and therefore thermal and kinetic losses from the overall potential, remembering that the energy it took to put it up in the top tank will never be yielded on return, Lets say its a 12v system so it takes (not anywhere near the real figure) 3kw of energy to fill that tank, my assumption if you use most conventional methods of generation you might yield 2kw of power in return due to the 30 something % loss you would likely incur trying to regenerate electrical energy..

Reason? you have multiple forms of energy, kinetic (the one you're trying to harness), Gravitational (a constant therefore a limiter to velocity/torque), Thermal (energy spent and converted due to the endothermic nature of friction)... now gravity as a source of propulsion is advantageous as its automatically a part of your system, however on the fill process its same value is a direct negative on your final energy gains, so this energy you discount from the get go. Kinetic energy or the force put onto the impeller or turbine is your only source of energy with the latter two being either neutral or a negative draw on your overall production. Given this, you would seek to make a generator/alternator that requires the least amount of both frictional and electromagnetic hindrance per kw/h, however I suggest that such generators/alternators would be low output as I dont see small light units producing the 1000's of watts of energy required to run household appliances, you could harness that energy I suppose but you would be in an immediate diminished return than if you had just resorted to battery storage in the first place.

this is without factoring in other issues like changes in environmental temperature and the losses of current from wiring and so on.

The other issue is that you have limitations on what water can provide without considerable mass, acceleration and thusly the velocity of the water is limited by factors such as the diameter of the piping not only out from the tank but into the lower tank, and that water cannot essentially be compressed so its flow per mass is going to be the same over the vanes of the impeller regardless.

[Ziege]

Actually i did some rough calculations.... (i could be wrong)

But i come up with 97 litres of water flow per second from a 100mm pipe. By putting an impeller in the way the flow rate will slow down. So even at half flow that 100k litre tank is not going to last 1hr of use.

thats if he even gets the L/min to fill the 100,000L tank in the first place, thats a lot of energy to begin with to ask of a solar system.

[on_one_wheel]

Lead acid battery banks are underrated in this day of whizz bang technology.

I have a friend who's house is off grid. It's powered by solar, wind with a back up generator for charging the lead acid bank.

His batteries are over 15 years old and still going strong thanks to properly managing draw, feed and voltage.

When they eventually stop performing they can be easily refurbished for half the cost of a new.

However, there's nothing adventurous in that... I'll be following your thread with great interest. As they say, nothing ventured, nothing gained.

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[Ziege]

Cheers MM. A lot of ppl are using creeks out the back of their properties to run old washing machine drums and things like that... it it’s hard to regulate the flow as it’s based on water coming from the sky.
In fact - one of the better whiskey destillers in this stste, Pete Bignell of Belgrove - powers his distillery from junk he has turned into power generation - it’s quite unbelievable to witness what he’s made...wind turbines from old plastic petrol containers that had holes in them, windows turned into solar frames, heaters from mirrors, etc etc - but his main power source is from his seasonal river - a hydro set up. I might run my idea bY him...he has enough money to do something with it if he thinks it has merit.

i mean the creek thing is a different kettle of fish altogether, you dont need to preload that and expect a return, you can even get low efficiency from the creek and still make it worth it depending on the size/depth/speed of current etc. In the end its all about volume, mass times acceleration = Force, this Force is the "work" or torque required to generate the electricity, so a deep fast flowing creek is a kickass generator, especially if it can be dammed and then a rotating assembly/turbine/impeller can be added to the gate of said Dam. but yeah different energy vs outcome than having to pump a large volume of water...

My issue with using smaller pipe to move water over the impeller over a longer timeframe, means you have significantly less Mass therefore less torque.

[Farmerpete]

Couldn't you use a ram pump to keep it circulating??

[TassieTiger]

I think you will run into too greater losses kw/torque wise, these direct mechanical losses are inalienable as you need some sort of "resistance" to induce a current.

Example, -
the alternator on your car makes energy in gross excess to the electrical needs of your vehicle, the amount of watts per energy at set amperage is way more than you would need, however the fuel source is not used efficiently by either the engine or the alternator, and the heat and other energy losses due to mechanical drag and friction are completely negligible because the exercise is making power, not looking for a certain yield of efficiency, likewise alternators HP/Kw scavenging isn't really factored into the overall energy/fuel consumption due to the necessity of its being there and the fraction of a percent difference it makes vs the losses of efficiency from the drive train and engine itself far outweigh it...

this is the inverse of your hypothetical situation, you would be looking to have as much efficiency vs output of your generator/alternator to yield the greatest return from your finite storage. however there is the inevitability that you will have multiple points of resistance and therefore thermal and kinetic losses from the overall potential, remembering that the energy it took to put it up in the top tank will never be yielded on return, Lets say its a 12v system so it takes (not anywhere near the real figure) 3kw of energy to fill that tank, my assumption if you use most conventional methods of generation you might yield 2kw of power in return due to the 30 something % loss you would likely incur trying to regenerate electrical energy..

Reason? you have multiple forms of energy, kinetic (the one you're trying to harness), Gravitational (a constant therefore a limiter to velocity/torque), Thermal (energy spent and converted due to the endothermic nature of friction)... now gravity as a source of propulsion is advantageous as its automatically a part of your system, however on the fill process its same value is a direct negative on your final energy gains, so this energy you discount from the get go. Kinetic energy or the force put onto the impeller or turbine is your only source of energy with the latter two being either neutral or a negative draw on your overall production. Given this, you would seek to make a generator/alternator that requires the least amount of both frictional and electromagnetic hindrance per kw/h, however I suggest that such generators/alternators would be low output as I dont see small light units producing the 1000's of watts of energy required to run household appliances, you could harness that energy I suppose but you would be in an immediate diminished return than if you had just resorted to battery storage in the first place.

this is without factoring in other issues like changes in environmental temperature and the losses of current from wiring and so on.

The other issue is that you have limitations on what water can provide without considerable mass, acceleration and thusly the velocity of the water is limited by factors such as the diameter of the piping not only out from the tank but into the lower tank, and that water cannot essentially be compressed so its flow per mass is going to be the same over the vanes of the impeller regardless.

Where would be the multiple sources of resistance and losses? Given the water would be cascading almost straight downwards towards a small impeller - maybe 2 impellers - from a height of at least 3m, the only resistance from production side would be at the generator and then losses from cabling ? Where would the mechanical losses be ?
I understand your concerns re torque vs diameter - but the thought I had in my head at least, would be the impellers would sit in a vertical position - cups if you will, spliced into an open section of 1” pipe - this cuts down water requirements and with a 3m head - increases weight / torque significantly. Very roughly - this might spin an impeller at at least a thousand rpms - roughly - and of course design would be paramount. Having it sit vertical resolves many current problems.
How much wind do you need to create 1000w from a wind turbine - 2metres per second...so effectively, you need water to at least replicate that and given water is an actual substance not a gas, you’d need far less of it.

Of course the up hill aspect - solar excess driving a dc pump to move water in daylight hours - that’s actually something I have in place right now...but I’m charging a battery direct rather than using excess power because it was available at the time - but it’s free power regardless...
And yes farmer Pete, your correct. That could work as well. - good thinking.

[TassieTiger]

This is done in several parts in Europe like Germany where they have some very high mountain lakes. They also use Hydro electric systems a lot on thier mountain rivers and streams. Even in some very small ones and small turbines for local city use. They will pump the water from a bottom lake to a mountain lake and then drain it to produce electricity when needed.

I did not know this Larry. This is exactly the sort of thing I was looking at - could it be made to work on a local, independent or community basis...?

[Ziege]

Where would be the multiple sources of resistance and losses? Given the water would be cascading almost straight downwards towards a small impeller - maybe 2 impellers - from a height of at least 3m, the only resistance from production side would be at the generator and then losses from cabling ? Where would the mechanical losses be ?
I understand your concerns re torque vs diameter - but the thought I had in my head at least, would be the impellers would sit in a vertical position - cups if you will, spliced into an open section of 1” pipe - this cuts down water requirements and with a 3m head - increases weight / torque significantly. Very roughly - this might spin an impeller at at least a thousand rpms - roughly - and of course design would be paramount. Having it sit vertical resolves many current problems.
How much wind do you need to create 1000w from a wind turbine - 2metres per second...so effectively, you need water to at least replicate that and given water is an actual substance not a gas, you’d need far less of it.

Of course the up hill aspect - solar excess driving a dc pump to move water in daylight hours - that’s actually something I have in place right now...but I’m charging a battery direct rather than using excess power because it was available at the time - but it’s free power regardless...
And yes farmer Pete, your correct. That could work as well. - good thinking.

thing is end of the day you cant make more energy than you have, over unity does not exist. so the idea is to store the water as energy, my issue with that is that the cost of moving the water alone = no excess energy from the solar anyway... as in you would end up with the expense and so on of more solar and more solar to try and even make the water tank/reservoir hold a equitable amount of water as stored energy,

yes you have multiple sources of loss/resistance the water itself being one of those. and a wind turbine has energy applied over distance = torque, very different to a 1" pipe flowing onto a small impeller, because heads up a 1" hose going onto a larger impeller (dimension wise) will create a zone of turgor resistance and minimise the flow even if vertically orientated. I am not going to do the math right now cos drinking beer and food on the stove, but the wind turbine at 2m/s is most likely going to be under many many times the force than your water turbine additionally its turning a much much much much much larger generator than your 1" hose could ever to aspire to propel, so that 1000watts is being generated over a much larger surface area ergo more current per revolution.

[TassieTiger]

[.[/quote]

thing is end of the day you cant make more energy than you have, over unity does not exist. so the idea is to store the water as energy, my issue with that is that the cost of moving the water alone = no excess energy from the solar anyway... as in you would end up with the expense and so on of more solar and more solar to try and even make the water tank/reservoir hold a equitable amount of water as stored energy,

yes you have multiple sources of loss/resistance the water itself being one of those. and a wind turbine has energy applied over distance = torque, very different to a 1" pipe flowing onto a small impeller, because heads up a 1" hose going onto a larger impeller (dimension wise) will create a zone of turgor resistance and minimise the flow even if vertically orientated. I am not going to do the math right now cos drinking beer and food on the stove, but the wind turbine at 2m/s is most likely going to be under many many times the force than your water turbine additionally its turning a much much much much much larger generator than your 1" hose could ever to aspire to propel, so that 1000watts is being generated over a much larger surface area ergo more current per revolution.[/quote]


*********
No one is trying to produce more energy than utilised - you don’t seem to understand the actual point of the exercise in using excess electrical energy to drive water up hill...you said your issue with this point is the cost of actually moving the water...? how would this need excess solar panels when most family homes are producing 5-10kw per hour excess during daytime hours whilst they are at work - and a 6m header pump needs 15 amps per hour only and will pump 70 litres per min ?

Re your other point - 2 metres per second of gas(wind) vs 2-3kg of water travelling at 9.8 metres per second - you can’t be serious to think that the wind will produce more force at that very low rate...you don’t need the maths for that.
With the impeller vertical, and designed for optimum flow, there can’t be any turgor resistance, as the CAD design based on weight / force would ensure impeller cups are spaced accordingly.
I get to work with wind turbines - some of the latest designs can start up at very, very low speeds - if you remove the vanes (vanes are counter productive - as whilst they offer power, they also present a lot of ex fluidity drag) and manually spin as hard as you can - they are still spinning a minute later - efficiency is quite amazing.

[Ziege]

youre missing a lot of points still... you have a 1" pipe, so you cannot run a large impeller, you simply wont have the weight/force to do it, it will essentially stall itself, so, issue you have is a torque issue, you wont turn a large generator like a wind turbine can because you wont have the inertial forces necessary, torque = force over distance. the wind turbine has massive vanes to its advantage, your 1" pipe does not.

[Ziege]

also peak power is only for 4 hours a day, so you essentially only have maybe 6 hours of useful pumping time, unless your array can follow the sun, but even then you only stretch it out a little. so you will end up with 60L per min max (less because impeller(s) and whatever else like joiners and so on) through your 1" pipe, you need to be able to use that low pressure (cos gravity only) feed to create energy, at 70L/m you will get a tad over 25,000L and that will only flow for 7 hours at 60L/min, I just dont see that kind of flow making much of any electricity

[TassieTiger]

youre missing a lot of points still... you have a 1" pipe, so you cannot run a large impeller, you simply wont have the weight/force to do it, it will essentially stall itself, so, issue you have is a torque issue, you wont turn a large generator like a wind turbine can because you wont have the inertial forces necessary, torque = force over distance. the wind turbine has massive vanes to its advantage, your 1" pipe does not.

Youve not answered water pumping up hill query - ? I don’t understand your concerns here??

As far as I understand it - A directional impeller cannot stall mate, it is being driven whether it likes it or not, especially vertical - how will it stall with water being applied at force constantly ? The residue water will be gone before next impeller blade comes round.
Don’t get hung up on the size of plumbing / it’s concept not design. But the question remains - how, does a free spinning impeller stall ? And why must it be large - if you can increase rpm instead ? Fact is - impeller / plumbing size would need in-depth calculations to optimise...but even my kids messing around with vanes taped on a bicycle wheel for experiment - pointing the measley garden hose at the bloody thing resulted in several hundred rpm lol.
Your wind vanes also offer massive drag - massive drag, and is why soft starts cannot be integrated on things like shed whirly birds...as above - I work with several wind turbines of various size (I’m assuming your thinking 10kw and Up that do require huge blades to turn - I actually work with 600w-2kw units with small blades or even lantern style) and they are problematic.... wind is hardly ever constant, so they need various smarts integrated and of course, brakes, variable microprocessors, etc - and..some days, it’s just not windy...with water, you can regulate flow and it would essentially be a free force...it just has to be made to work...which is the debate I guess - as to how...but it has to be concept - before design regardless...it’s why many ideas never see light of day...

[Ziege]

stalling doesn't mean stopping, its just a general term for the lack of action, in any case I understand entirely your concept, but dont see it working in the slightest myself, not in any equitable fashion. remember perpetual motion is mathematically possible but not a reality. so even if you get it working as a thought experiment its not guaranteed to work

[Ziege]

also you cant increase the rpm, youre employing a constant force

[Ziege]

the pizza and beer is making it too hard to type but there are a lot of issues still at large in the entire system