Electricity needs when the grids down.

[Pete Grey]

While we are in lockdown/self isolation i intend try and test as many of our preps as possible, so here are my thoughts on electricity, and our preps.

I think it’s most important to work out what your electricity needs might be in a grid down situation, and try to balance perceptible needs with what you want to spend or what you can afford.

I don’t mean try to run your home at the same level as on the mains, but at a level that suits your plans at a price you can afford, and to give you some flexibility. Our plans are quite basic. As seasoned campers we can mostly live without mains electricity.

However if we were of an age where we could guarantee twenty years of use of a full off-grid solar system we would not hesitate, but we are both in our mid seventies, in reasonable health at the moment but who knows what the future will bring.

So these are our thoughts, I don’t intend to attempt to run the freezer on solar, this would be a huge electricity drain on any system and would need a fairly large array and a large financial commitment, which we have ruled out.

A generator running a few hours a day would keep it going, but you have to store fuel and the noise could draw attention, even so s/h genny’s can be cheap (a couple of months ago i was offered an old honda ec2200 for £50, i nearly snatched the guys hand off).

This is completely different from my previous plans, which were as the freezer packs up just to dry-salt or brine food as it thaws if we don’t want to or can’t eat it immediately.

Another high user of electricity is laundry, we keep plenty handwash detergent, and we are on the lookout for an old fashioned mangel/wringer.

For our needs all we want is charging for 12v batteries (leisure and vehicle) usb devices, AA and AAA rechargeables, these are our very basic requirements for led lanterns , cb, walkie talkies, flash lights etc.

All house lighting is now 240 volt led and can be run from the genny or a leisure battery and an inverter, not indefinitely but for a couple of hours while we assess the situation, and decide if it’s a short or long term event.

For our main charging needs we have a 100 watt folding solar panel with built in charge controller, good summer sun gives us 6-7 amps, quite useful, i haven’t tried it in winter weather i expect only 1-1.5 amps, so we will probably get a second one. These will be used to charge our leisure batteries (we have two) or any vehicle battery as necessary.

We also have a couple of 20 watt panels (and an old 5 or 10 watt, can’t remember which) which will be used mainly to charge usb devices and the AA and AAA rechargables. We have two 12 v 7 Ah sealed batteries out of an emergency lighting system these are gaffer taped together and wired to a cigarette lighter socket as a portable CB power supply.

These are our current electricity plans.

[Straight Shooter]

Very short term would be generators ,solely for freezers and gas boiler controls . Solar setup 1 is a 50 watt panel for USB ports and 750 watt inverter ,solar setup 2 ....3 100 watt panels 3 deep cell leisure battery bank good charge controller and a good quality inverter.....12 volt dc water pumps 2 off 12 volt dc Emerson water heating coil , 12 volt switches , connectors , cables , led lighting , fold out solar panel, crimping set and shrink tubes all sizes .....I was going to setup S2 in a purpose built greenhouse/shed but we intend to use this in a BO situation so undecided .
A few years back HIGHLANDER gave a good tip on this forum regarding freezers ....using a timer to control the use and running where he calculated the run time /against the down time a freezer could operate efficiently by turning off the supply for a few hours with no negative effect on frozen foods so long as it is in opened , a bloody good tip !

We also have facilities for charging double a and triple a and most others , a power pack with inverter Built in torch USB ports and 240 volt point .

From a washing cloths point of view .....some good metal calv buckets and a good scrubbing brush , and a good washing line .......we got em all ! .

[bigpaul]

Human beings lived for thousands of years without electricity, in fact electricity in homes in the UK didn't happen until the early 1930s- there were some in factories before that but not houses, some had gas, I remember my grandparents having gas lamps.
so electricity is a fairly new invention, less than a century old, but unfortunately we don't have enough generating capacity in the UK, for several winters we have nearly exceeded the supply only avoiding it by buying in extra supplies from the continent, as EDF(French) now seems to run our national electric supply I don't think we can rely on them in a crisis.
home generation is only possible whilst the infrastructure is viable, solar panels may and do last 2 or 3 decades the stuff that they plug into dont, once a spare part is needed the thing is no more than scrap use.
it is possible to live without electricity, its just a matter of adapting, but with most people relying on such infrastructure for their daily needs without any skills and knowledge to live any differently I fear the survival rate is destined to be very low.

[Straight Shooter]

Good points BP ....I have oil lamps and the oil to last months , a wood stove with loads of firewood and woods full of trees, as far as generators I have four and fuel , oil etc , seeds , tools, in order to feed us .....I too remember my grandparents using one oil lamp for the whole farm house and a fire range for cooking ,heating and nothing else ...no electricity supply ...at all....the solar set up I have is for coms and charging batteries and one freezer , and you are right ...when they fail they fail as with anything ....but I intend to make good use of what I have until such time I can’t .....and when that time comes I can go back to the times when there was nothing , I have made it my business to find out how! And so should anyone else on here.

[bigpaul]

when past civilisations collapsed the technology was so simple that the survivors could access their daily needs by their own physical labours and just just sit back and wait for society to reassert itself no matter how long this took, sometimes centuries, modern civilisations notably western ones cannot do this anymore, we have built a world wide supply system that is so fragile to disruption that it will collapse easily. many people cannot live without their technology and modern services and utilities.
once this civilisation collapses and make no bones about it it WILL collapse its more a matter of when, and for that one should look no further than daily events that are happening now.
when this happens the only ones that can survive will be the people that are self reliant, anyone who relies on the government or NGO for succour and support is going to be out of luck.

[Lightspeed]

I like the way that Pete is set-up. It covers the essentials.

We've just adding a petrol generator to our set-up as we’re vulnerable in the here and now to winter power outages, that would disable our heating furnace and central heating system.
We decided on a 3kw electric start gen-set, feeding the Furnace and CH pumps through a dedicated circuit.
I’m concerned that the Furnace / CH microprocessor controller might not appreciate the rough power coming from the gen-set, so have found an appropriate rated multi-function pure sine inverter to keep it happy.

The inverter, although un-planned, can also control a 3kW PV array, and will give us an effective UPS solution keeping the furnace operational for 8 hours or so from our back-up battery supply. (useful if outage occurs overnight)

Daily fuel consumption using the Gen set 16hrs + 8hrs running from the battery bank is going to be around 20L of petrol per day, so somewhat expensive and not viable as a long term solution.

[Pete Grey]

In a major power outage we too would lose our gas central heating, we would then use solid fuel (smokeless coal) for heating in the wood burner/multi fuel stove. We WILL manage very well.

In a SHTF long term situation the gas supply would also be off as well as main electricity so no CH anyway. We can boil on the top of the stove but most cooking will be done by propane.

With our setup there is no way we could run the central heating long term by batteries and inverter, and our genny will only be used for short periods from battery charging when we can’t use solar power. We would benefit from an extra 100W panel to help charging over poor winter sunlight levels.

[Lightspeed]

Pete, I get what you're saying. Even though the CH control and pumps only consume a few watts, its a few watts 24hours a day. To keep it running in winter would need around 1kW of solar generation power + scaled battery storage to see the system through the night.

Here's a useful tool to calculate PV output from you location, orientation and pitch of solar array: https://pvwatts.nrel.gov/pvwatts.php

[Pete Grey]

LS very useful calculator...........so December only gives a fifth of the July power.

I suppose this is due to the reduced hours of sunlight as well as the sun lower in the sky and sunlight having further to travel through the atmosphere.

So what ever is your perceived minimum requirement for battery charging, you need five times more.....hmm.

[Lightspeed]

Hi Pete,

You're exactly right. Plan minimal consumption needs and scale PV array based on mid winter predicted output.

For me, a 3Kw array will be fractionally short of the 200w/h that my furnace and CH system will draw in mid-winter.

We're working on this basis as in the here and now, we'll be able to meet the shortfall from mains / backup generator. If a long term crisis were to unfold, the furnace and CH system would be shut down in order to conserve fuel, leaving a useful minimum 2.4kW/hr per day of off grid power.

Highlander's excellent real world advice a few years ago, was that in summer used excess generated power through time switches ( on while daylight and generating, off overnight) to feed immersion heaters, fridges and freezers etc. This uses self-generated power to directly replace mains consumption.