Off grid Power

[oldclaypaws]

A previous thread morphed from chainsaw mills to discussions of tools and generators, which raises the whole interesting question of having electric power off grid, a very interesting and worthy topic.

Anyone with an isolated wood who may need power will be interested in learning about the options of how to generate your own power, be it from generators, wind or solar.

Simon mentioned the following;

I have successfully charged batteries when away from the mains using an inverter and a 12-volt power source such as leisure batteries. A pure sine wave inverter is I think needed to operate the Makita charger properly.

I recently bought a generator (http://www.thegreenreaper.co.uk/Generat ... .4KVA.html) which I'm very pleased with. Note the voltage regulation feature which means it should be able to drive anything upto the power rating including items with 'sensitive' electronics (such as the Makita charger for instance). Note also the headline rating of 3.4kVA, not to be confused with the maximum wattage of the items it can power (2700). My best tip for generator use is a long cable so you can site the (noisy) generator away from where you're working. This one by the way adequately drives my 2200 watt electric log splitter

I chipped in thinking a diesel generator might be more cost effective as they can run off Red Diesel at a cost of around 67p / litre / hour.

I personally hadn't realised you can use 12v leisure batteries to power 240v devices, using an inverter. This then leads on to the question; if you had a 'green' source of power, such as a wind turbine or PV cells on a South facing roof (an option for me), couldn't you theoretically trickle charge a bank of 12v leisure batteries off a PV panel on the roof, then power any 240V tools or other devices using an inverter, hence being off grid and having 'free' solar 240V power? Sounds expensive to set up, but cool if viable.

How else does anyone else generate their power when required in their wood ?

[SimonFisher]

I chipped in thinking a diesel generator might be more cost effective as they can run off Red Diesel at a cost of around 67p / litre / hour.

Those that are already familliar with my thoughts on fuel for such things won't be surprised to learn that I run my petrol generator on Aspen alkylate (http://www.aspenfuel.co.uk/clean-facts/aspen-v-premium-unleaded/) which puts my fuel at somewhere nearer £3.60 a litre but does make the fumes a bit less noxious and means I don't have to worry about the effects of gone-off fuel in the engine.

[SimonFisher]

I personally hadn't realised you can use 12v leisure batteries to power 240v devices, using an inverter. This then leads on to the question; if you had a 'green' source of power, such as a wind turbine or PV cells on a South facing roof (an option for me), couldn't you theoretically trickle charge a bank of 12v leisure batteries off a PV panel on the roof, then power any 240V tools or other devices using an inverter, hence being off grid and having 'free' solar 240V power? Sounds expensive to set up, but cool if viable.

That's pretty much how off-grid PV system are put together.

See these articles on Mike Pepler's blog: -

http://peplers.blogspot.co.uk/2011/04/eco-refubishment-installing-off-grid.html
http://peplers.blogspot.co.uk/2011/04/eco-refubishment-installing-off-grid_11.html
http://peplers.blogspot.co.uk/2013/07/off-grid-solar-pv-upgrade.html
http://peplers.blogspot.co.uk/2014/04/off-grid-solar-pv-upgrade-750w-to-1250w.html

[Meadowcopse]

I've been looking at complete stand alone system packages used on canal boats.
A high current capacity12 volt system combined with up to 1kW 240 volt AC option is tempting...

http://canalsidesolar.co.uk

I'd be quite happy with a consistent 150 watts at 240 volts for the slow-cooker

I still haven't ruled out a conventional single phase 240 volt 80 amp metered supply, but will await planning implications for the site and unrelated development and infrastructure going in across the road first

[Dexter's Shed]

ours is a much smaller scale set up, two solar panels from maplins, fixed to the inside windows of caravan, trickle power into the leisure battery, it then powers the lights/radio etc when were there, I have often looked on you tube at build your own wind turbines, would be nice, but so far we have not needed electricity, I'd be a little worried that if we had it on tap so to speak, we would loose the feeling of being away from the mad world as we do, as everyone who visits would then be bringing laptops and gizmo's

[smojo]

Just a word of warning for anyone thinking of using 12 leisure or car batteries. A lot of people think that 12dc is pretty harmless. You can put your hands across the terminals and won't get a shock. But batteries can deliver lots of current (amps). Shorting them out accidentally will create huge sparks, flashes and bangs and melt metal and if it's a piece of conducting metal on your wrist or clothing that causes the short, it can seriously burn you or even blow your hand off. Working in telecoms I have known of folk who were wearing a ring and shorted some dc equipment and it took the finger straight off. So handle with great care.

[oldclaypaws]

A local oil supplier confirmed today that its quite kosher to use red diesel for generation, and they'll sell a minimum 55 litres (about £30 worth/ 10 gallons) if you roll up with a couple of plastic drums to be filled. At a cost of around £5 a day for lecky, its quite an attractive option.

Not sure if Simon has shares in Alkylite fuel, but forking out six times as much for your juice does seem a tad extravagant, or beyond the budget of we humble artisan craftsmen. I guess the ideal is finding a steam engine, powered by brash, which makes an attractive low chundering sound, generates 3KV+, and is neat for pulling logs or driving a saw mill on a PTO to boot. Traction engine? Also makes the commute home more interesting, if a bit 'wearing' on the tarmac.....

[Wendelspanswick]

I buy red diesel for my tractor from Western Fuel straight from the pump in either Taunton or Bridgwater, 25 litres works out at about £21.

[ballibeg]

Red diesel ruled out for me in my tractor as I do deliveries with it.

Right mine field of illogical cans and can'ts!

Dave

[oldclaypaws]

Cheers, useful to know. Not sure if the frequently quoted current '66p/litre' is ex vat or bulk 1000 litres, £21 for 25 litres = 80p+, which is a premium on the much quoted 66p, but still a lot better than petrol.