what setup would I need for basic "off-grid" living

CamperMan

Hi,

what sort of system would I require for off grid living, I calculated that I would use on average 160 daily amp hours..

What wind turbine / solar panels should I use?

Thanks

quentingargan

160 Ah is a lot of juice for a renewable energy system. Wind and solar systems are capable of producing that amount of power over a year (14 MwHr) - probably a 6kw machine would do that - but your real problem is storage which is inefficient. At 48V, a battery system would need to store about 1,000 Ah for each day of no wind.

Are you sure you want to be off-grid? If so, are there items in there that you are using electricity for (cooking, boiling kettles, heating water - anything to do with heating) that would be better done with another fuel?

We have lived off-grid for the last six years, though we can "cheat" as there is grid on our farm buildings and if the telly goes off we can flick a switch. We have a fridge, freezer, washing machine, telly, lights, computers etc. like a normal house, but never use electricity to generate heat. (We fill the washing machine manually with hot water from a solar panel or wood burning stove).

We have a 2.5kw turbine and about 1,200 Ah of batteries at 24V. Our lights run directly off the 24v as we wired the house using stranded wire for that purpose. We have an old Trace inverter for the other items, though I think modern ones are more efficient than ours.

Q

CamperMan

Thanks Q..

It's for a holiday log cabin where the only use would be 12 v lights, a couple of hours a day of TV, a couple of hours a day using the laptop, and running a fridge. There isn't a washing machine, tumble drier, electric kettles, etc.

Heating will be using a pot bellied stove, cooking will be with gas.

Thanks

CamperMan

we got a 1000w wind turbine and 1600ah batteries... setting this up should keep me busy for a while

quentingargan

Brave move. Good luck with all that.

Carlow52

CamperMan wrote: »

Thanks Q..

It's for a holiday log cabin where the only use would be 12 v lights, a couple of hours a day of TV, a couple of hours a day using the laptop, and running a fridge. There isn't a washing machine, tumble drier, electric kettles, etc.

Heating will be using a pot bellied stove, cooking will be with gas.

Thanks

Looks to me like a lot of juice: u really need to look again at the usage requirements and perhaps run the fridge off the gas while u are there: the fridge is a beast for consuming power.

AAMOI: what Power/current figure have u got for all the appliances.

CamperMan

Carlow52 wrote: »

Looks to me like a lot of juice: u really need to look again at the usage requirements and perhaps run the fridge off the gas while u are there: the fridge is a beast for consuming power.

AAMOI: what Power/current figure have u got for all the appliances.

calculated it at about 400w to 700w per day for lighting small TV, laptop and a small chest freezer converted to a fridge (seems to use less energy than than a standard fridge)

Carlow52

Thanks.
You don't need me to tell u this but the difference between 400 and 700 will have a hugh bearing on the storage costs.

I trust u have done the research on battery life, number of cycles etc as well as the need for good charge up/draw down controls and when they talk about deep discharge it means max 50% so if u need 1600 Amp hr ur battery pack will be min 3200:)

Ventilation, over heating, over cooling are all considerations also

quentingargan

I have yet to see an off-grid system that doesn't need some sort of back-up occasionally. However, a diesel generator used occasionally will work quite efficiently if it is powering a battery charger that keeps it working on full load. You should be able to pick up such a charger secondhand from electric pallet truck companies.

It is better to use this generator occasionally than to leave the batteries sitting at a low level. If you have a water cooled genny and use the heat from it within the house, you will probably be working on better efficiency levels than the ESB gets to in its power stations where the heat is used to warm the crows!

I have a hunch that even fork lift batteries are meant to be recharged each night, and not left on 10% or 20% of their charge for too long. Their normal cycle is that they get recharged each night. Batteries will last reasonably well if you keep to within their limits, but few off-grid systems seem to do that...

By the way, I got a few 12V CFL bulbs a while ago. You can have them at cost if you PM me. But they don't like running at above 14V.