Off grid power project

[ImLost]

Excuse the quick sketch! (bored at work )
Hopefully the pic helps explain a bit about what I'm trying to achieve.

I have a piece of land which is off grid that I'm hoping to rear some calves on.

Water isn't so much a problem as I have a well and plenty of rainwater.

However, power I have none of. I also have no idea what I need in order to get enough power. Ideally I would need to store power (hence the battery) for use at night, especially if I was to use solar as a power source. I would also ideally need to run lights/appliances off standard sockets and if possible through timer switches so that I can start heating water etc. Before I arrive to do the feeds.

I'm not an electrician and not overly practical, so would appreciate some help! I did figure out a few bits and pieces I could possibly pull together but then get confused with how many Watts etc I'll be producing/able to store/voltages in/out etc.

Budget also isn't huge, but could stretch it if the system was to run smoothly. I also haven't ruled out the thought of a generator, but don't know how to get round the idea of timer switches without having the generator running constantly.

Suggestions appreciated!

 

[Still Farming]

Navitron forum is no more

Apologies if this is inappropriate, but I suspect several here, like me, also frequented this forum, which has now sadly closed. A shame, as while greenbuildingforum is excellent, Navitron had a somewhat wider focus to cover topics such as electric vehicles etc. A sad, sad, loss.

www.greenbuildingforum.co.uk

May help you also
Navitron forum but could be down for some reason
For All about what you plan.

 

[Still Farming]

What are you heating?
Shed/caravan/tent?
Lots of low energy led lights and items about for 12v 24v and 240v these days.

 

[ImLost]

What are you heating?
Shed/caravan/tent?
Lots of low energy led lights and items about for 12v 24v and 240v these days.

The heating will actually be a water heater of some description, for mixing calf milk, so could suck a lot of power.

 

[Still Farming]

The heating will actually be a water heater of some description, for mixing calf milk, so could suck a lot of power.

If feeding a stack of them, not so much if half a dozen??

 

[ImLost]

If feeding a stack of them, not so much if half a dozen??

Let's just say I hope to do a few more than half a dozen

 

[Still Farming]

Let's just say I hope to do a few more than half a dozen

May struggle then.
Biomass boiler?

 

[TechWise]

Solar is a very mature technology for these sorts of setup. You could do a setup like this using off-the-shelf components. PV panels, MPPT charge controller, inverter and plenty of batteries.

Some good reading here https://www.greenmatch.co.uk/solar-energy/solar-system/5kw-solar-panel-system although you wouldn't be grid-connecting, you'd just charge straight into batteries.

Going by the figures in the article, a 5kW PV array will generate 20kWh of energy on a good day.

For reference, a household kettle is about 2kW (it might be a bit more, but let's stick with easy counting). Your 20kWh harvested during the day would run the kettle for 10 hours, or two kettles for 5 hours, or 4 kettles for 2.5 hours and so on. So actually, with a 5kW array, you could produce quite a lot of hot water. That's assuming you have the battery capacity to store 20kWh.

Let's say it's a 48V battery pack, so 20kWh / 48V = 400Ah. Say a big leisure/caravan type battery is 100Ah, you'd need 4 in series to get you to 48V and four in parallel to give you the storage capacity, so 16 batteries.

Of course, all of this assumes 100% efficiency throughout the system and that the batteries never age. In practice, you'd want to up all of those figures as much as you can afford. The recommended derating amounts for lead acid batteries is probably online somewhere if you want to delve right in.

 

[Pigken]

Be a bit unsure of rain water for mixing milk, is there not possible salmonella issue from bird sh!t on roof. Some one may know different . Love the diagram, have thought of similar before. But often come back to using gas stove of some description for heating water.

 

[Still Farming]

Solar is a very mature technology for these sorts of setup. You could do a setup like this using off-the-shelf components. PV panels, MPPT charge controller, inverter and plenty of batteries.

Some good reading here https://www.greenmatch.co.uk/solar-energy/solar-system/5kw-solar-panel-system although you wouldn't be grid-connecting, you'd just charge straight into batteries.

Going by the figures in the article, a 5kW PV array will generate 20kWh of energy on a good day.

For reference, a household kettle is about 2kW (it might be a bit more, but let's stick with easy counting). Your 20kWh harvested during the day would run the kettle for 10 hours, or two kettles for 5 hours, or 4 kettles for 2.5 hours and so on. So actually, with a 5kW array, you could produce quite a lot of hot water. That's assuming you have the battery capacity to store 20kWh.

Let's say it's a 48V battery pack, so 20kWh / 48V = 400Ah. Say a big leisure/caravan type battery is 100Ah, you'd need 4 in series to get you to 48V and four in parallel to give you the storage capacity, so 16 batteries.

Of course, all of this assumes 100% efficiency throughout the system and that the batteries never age. In practice, you'd want to up all of those figures as much as you can afford. The recommended derating amounts for lead acid batteries is probably online somewhere if you want to delve right in.

Also he is vague on his budget so may cost too much?

 

[tw15]

What about using calor gas to heat the water that would reduce the power requirement by a lot .

 

[ImLost]

What about using calor gas to heat the water that would reduce the power requirement by a lot .

I have thought about making my own AD plant, but I don't know how consistent it would be in the winter.
Also, how would you get gas to turn on/light etc from a timer? I assume it can be done as gas ovens often have timers.

 

[ImLost]

Also he is vague on his budget so may cost too much?

As I say, budget is tight ish, but no set budget, because if I found the right system that was super efficient and did exactly what I wanted, then I would be prepared to pay more.

 

[ImLost]

Be a bit unsure of rain water for mixing milk, is there not possible salmonella issue from bird sh!t on roof. Some one may know different . Love the diagram, have thought of similar before. But often come back to using gas stove of some description for heating water.

How about well water? I'm not sure off the top of my head what temp salmonella can survive? Will have to check it out as I had been concerned about it.

 

[Bury the Trash]

don't discount solar thermal ( not just pv ) for heating water, even low sun conditions it can take the edge off water, neighbour has had it for 30 odd years or so, must be long lasting panels

 

[ImLost]

don't discount solar thermal ( not just pv ) for heating water, even low sun conditions it can take the edge off water, neighbour has had it for 30 odd years or so, must be long lasting panels

I noticed a couple of cheap systems when I was scouting around. Might be worth a look as an extra add on.

 

[tw15]

I have thought about making my own AD plant, but I don't know how consistent it would be in the winter.
Also, how would you get gas to turn on/light etc from a timer? I assume it can be done as gas ovens often have timers.

What i was meaning was to use solar or small wind turbine for running lights and use propane gas to heat water and cook with you don,t need to have such big draw of power then as lighting could be 12 volt led. Hope that makes sense .

 

[Blackleg]

Free Hot Water from Compost Wheelie Bin - The Permaculture Research Institute

Here’s a great tip given by a member of the Aquaponics Made Easy Forum on a cheap easy-to-buil

www.permaculturenews.org

 

[ImLost]

View attachment 980811

Free Hot Water from Compost Wheelie Bin - The Permaculture Research Institute

Here’s a great tip given by a member of the Aquaponics Made Easy Forum on a cheap easy-to-buil

www.permaculturenews.org

What temp would that get too?

 

[Blackleg]

What temp would that get too?

No idea, read your post and thought I'd had a Eureka moment!
Quick google showed it's already been invented the article says a scaled up version allowed thirty people to shower and wash up, suppose it depends on how good the compost mix is.