Offgrid Living.

[Wendelspanswick]

Hopefully @HughF can provide some insight as I know he lives off grid.
Getting to the stage where we can start using the barn but two hurdles to overcome are there is no mains power or water.

I'm going to use rainwater collection for everything but drinking, using the roof runoff and passing it through a sediment tank then a slow action sand filter into an underground storage tank then pump it up to a roof space tank. This will be used for washing etc.

For power I was going to stick some solar panels on the roof, should be able to get a 6kw array on the roof.
For the rare occasions (sic) when the Sun fails to make an appearance I have a 15KVA PTO generator which can provide a 63 amp 240V supply plus I also have a small 3kva Honda generator.
I really need to come up with a system to store the power so I need a battery array and some method of controlling the inputs and outputs.

What batteries to go for, old tech or new?

How to monitor and control it all?

Reading up on off grid solar they seem to talk about either 36V or 48V systems, do you then transform this down to 12V for a lighting circuit or use an inverter to produce 240V?

Any info gratefully received.

 

[Burdekin]

Our beach house in Oz was off grid. Rain water was used for drinking and bore water for washing. We originally had a generator for lights but this was later changed to solar, we only ran lights and the TV from solar. Cooker was gas bottles and the fridge was a very old Kerosene (paraffin) fridge which worked amazingly well.

 

[Wendelspanswick]

I have an endless supply of firewood so I'm going to either buy or build a wood stove with hotplate, oven and back boiler so that's water heating and cooking sorted, hopefully I can dump some energy from the solar into the hot water tank but not sure how to do this with a 36V/48V DC system.

 

[HughF]

I use outback power systems products, other similar products are available from trace and sma. I can only vouch for the outback stuff as I have no experience with the other 2.

Go 48v... is this system to be used for temporary light and power or full time working? That determines battery type (trojan t105 for light use or more expensive for heavy use).

Expect to be in 3k for inverter/controller/mounting hardware. Panels are cheap these days. Batteries are also surprisingly affordable, ask @MattH who bought a complete new pack for his forklift recently.

Happy to talk on the phone if you want, pm me.

 

[Wendelspanswick]

In theory I could also use the rainwater for drinking but a.) I can't see myself using more than 2 litres of water for cooking and drinking a day and b.) I would want to test the water before drinking and it's another hassle. It will be easier to either buy in a few bottles of water or fill up my own bottles when I'm out and about.

 

[Burdekin]

My dad made the simplest of shower hot water systems that worked a treat. All it was was a tube that acted as a flu that was vented out the roof and inside the tube he wound copper tubing which connected to the shower and all that heated it was cloth soaked in paraffin. It was so simple, might get tiresome to use all the time.

 

[HughF]

Regarding your question on 12v lighting, we ran this way for 20yrs, definitely stick with inverter and modern led/ccfl lights. The old 12v system was a right pain.

 

[Wendelspanswick]

I use outback power systems products, other similar products are available from trace and sma. I can only vouch for the outback stuff as I have no experience with the other 2.

Go 48v... is this system to be used for temporary light and power or full time working? That determines battery type (trojan t105 for light use or more expensive for heavy use).

Expect to be in 3k for inverter/controller/mounting hardware. Panels are cheap these days. Batteries are also surprisingly affordable, ask @MattH who bought a complete new pack for his forklift recently.

Happy to talk on the phone if you want, pm me.

Do you dump the solar into a hot water tank once the batteries are up to charge?

 

[HughF]

Do you dump the solar into a hot water tank once the batteries are up to charge?

At the moment, no. But we should...

 

[Burdekin]

In theory I could also use the rainwater for drinking but a.) I can't see myself using more than 2 litres of water for cooking and drinking a day and b.) I would want to test the water before drinking and it's another hassle. It will be easier to either buy in a few bottles of water or fill up my own bottles when I'm out and about.

There is no pollution where our house is in Oz so can't comment, but we've been drinking rainwater unfiltered there since I was born with no issues. We don't get the same amount of rain there so it was more precious than here. The bore water was harder but fine for a shower etc.

 

[HughF]

Today's output... more would have been harvested if we had a dump load running the panels at mppt all day. Probably were in float by mid morning with this sunshine.

 

[Wendelspanswick]

I would be tempted to get a bore drilled but we are on top of a hill and the local geology is fractured sandstone/mudstone so I'm guessing the water table is a long way down.

 

[addjunkie]

For water can you not just mole a pipe in...how far is it. For heat / hot water, its quite common if you keep your eyes open log burners with back boilers or solid fuel rayburns come up for pennies.

Ive been looking into this eco off grid power, its bloody expensive, to do it properly.

 

[gaz1]

In theory I could also use the rainwater for drinking but a.) I can't see myself using more than 2 litres of water for cooking and drinking a day and b.) I would want to test the water before drinking and it's another hassle. It will be easier to either buy in a few bottles of water or fill up my own bottles when I'm out and about.

if i was going that way id be looking at the esse system as the design is simple for a rocket stove cooker

im also up to making a rocket stove boiler thats in the planning stages at moment but have already chosen its design base untried or untested

 

[Wendelspanswick]

if i was going that way id be looking at the esse system as the design is simple for a rocket stove cooker

im also up to making a rocket stove boiler thats in the planning stages at moment but have already chosen its design base untried or untested

Have you got a link?
I've seen the Esse Ironheart:

Edit:
Gulp! Just seen the price of the Ironheart, £4000!!!

 

[Luke]

For what it's worth, we're on-grid, but at the moment typically dumping 10KWh a day in to the immersion heater in the hot water tank from a 3.24 KWp array.

The house is zero-import from about 0730 until 1900 ish.

 

[Wendelspanswick]

For what it's worth, we're on-grid, but at the moment typically dumping 10KWh a day in to the immersion heater in the hot water tank from a 3.24 KWp array.

The house is zero-import from about 0730 until 1900 ish.

Ours is currently winding the analogue electricity meter back!
The difficulty is that with an on grid system it's easy to dump the surplus into the immersion as the inverter kicks out mains AC electricity, with an off grid system you output DC for battery charging then you use an inverter for AC.

 

[8ob]

I would be tempted to get a bore drilled but we are on top of a hill and the local geology is fractured sandstone/mudstone so I'm guessing the water table is a long way down.

Is a wind turbine an option as you are on top of a hill?

Bob

 

[Luke]

More cost-effective than any FIT!

A PWM controller, a few solid state relays and a bank of 230V immersion heaters would do the trick at 12/24/48 volts. In fact, as the resistance will be too high, the heaters could be switched in on a cumulative basis, based on battery voltage or charge current.

 

[ukracer]

Ours is currently winding the analogue electricity meter back!
The difficulty is that with an on grid system it's easy to dump the surplus into the immersion as the inverter kicks out mains AC electricity, with an off grid system you output DC for battery charging then you use an inverter for AC.

Cant you do both???