Emergency Lighting

[Joe]

So my first pass at the power issue is to provide emergency lighting that actually works and is 100% reliable.
So this is a run down on a pretty basic and easy to put together system.

1. The lights
I opted for LED as they give a very good light output for very little power consumption. This is the unit’s I have gone for.
https://www.ebay.co.uk/itm/265138113507?...%7Ciid%3A1

[Joe]

2. Power Storage
This might seem overkill but I might be adding more to the system later. The storage system will compromise of four 100AHr batteries so this will give a capacity of 12v at 400 Amps for 1hour or in this case 1amp for 400 hrs.

[Joe]

3. Charging
To start with the plan will be a basic 12v charger with trickle charge capability, however I might add to this in the future. The battery bank will draw a lot of current when the system is flat so I would like a more intelligent system that can deal with this. In addition I might add some basic solar charging to the system with a small 50w panel that shouldn’t need any regulation with the size of battery pack, it’s mainly a back up and can be added to during a longer event.

[Pete Grey]

Joe, before you spend more money work out you needs.

Are you planning for blackouts, three or four hours, or for total grid shutdown ?.

Generation is the most important, a folding solar panel, portable and comes with charge controller (sockets for usb devices) and battery leads, from £120, for a 100w panel.

If you’re just using usb rechargeable led lamps you don’t need four batteries, a single leisure battery, about £80 will be fine. A battery charger/ maintainer for when you have power, from £15, is useful, can also be used your BOV to keep the battery at peak condition.

These modern rechargeable usb lights with built in lithium batteries (we use Letour lights) will last a few days on a full charge, do your maths and work things out.

[Joe]

Pete the system is over specified because more will be added as I go along.
Having analysed the situation of losing power the big thing is being in the dark, once you have light the situation improves dramatically.
The next stage is looking at freezer back up and possibly a tv and WiFi supply. I’m not too worried about heating at this stage as you need significant power for that.
I would highly recommend the lights I have specified, for 4w the light output is amazing. Even someone building a simple system can hook one of these up to a 7Ahr battery and have a room sorted for 24hrs.

[Mortblanc]

Joe, a day is only 24 hours long.

If you need three weeks charge saved up in the battery banks then solar is not the best generation method for you. You will never have enough sunlight to fully recharge except in summer, when you really don't need it.

This is one of the scams of the greenies. Solar is not suitable for powering large parts of our globe. England happens to be in one of those areas.

If you don't need a charge controller then you are not producing enough power to refill your cells.

If the total grid is down then shining like a lighthouse on a mountain is pure suicide from a security point. When the sun goes down you need to have the lights off and go to bed, just like everyone else. Don't try to live then as you do now, set yourself apart and draw attention.

If you are thinking about partial power cuts, or rolling brown outs, a simple 12v charger on a single deep cycle battery with 100-200 amp hours will power your LED lights until the power is back on tomorrow, or the day after.

You simply have to plan your day and heavy power needs, around when the power is available.

[bigpaul]

in a minor power cut, a few hours, lanterns, flashlights and even light sticks will suffice, or just go to bed a bit earlier and wait until daylight.
in a total collapse all windows need to be blacked out-like in WW2.

[Joe]

MB I have the batteries here and they are only a few month old so might as well use them. The solar is only a back up, the system with be charged with a 240v to 12v psu/charger.
The over spec is so that I can add to the system.

[Pete Grey]

Both MB and BP bring up valid points, you do not need 24/7 power for lighting, just a few hours of an evening.

If your batteries are not identical they will not charge evenly, and you will need a powerful charger, at least 20amp.

If you’re running a lamp which draws 1amp for 6 hours (say 4pm-10pm of a winter evening) and your solar panel (100w) only gives you 1.5amps for 4 hours (10am-2pm lightest part of the day) you’re maintaining the status quo any more power for charging your phone etc is a bonus.

Our new system is two 120w panels charging two identical leisure batteries through a 30amp charge controller. At the moment plenty power for our needs.

The 100w folding panel (bought for the camper) charging one leisure battery is backup.

[bigpaul]

in the summertime its light until quite late, there is a reason most power cuts are in wintertime as that is when the most demand is and demand will outstrip supply.
as for long term power outage, I'm talking months here, not hours or days, and probably the grid is down permanently, a different sort of life style will be needed and we will be spending most of the daylight hours outside.