Battery Bank For An Off Grid Solar System
The heart of an off grid system are the batteries
The first thing that you want to get right when setting up an off grid system are the batteries. These is the most expensive part of the system and it is also the most vulnerable.
All batteries sulphate over time. Harderned sulphate molecules cannot take part in the energy exchange. In addition they also form a layer over the active material below insulating it from the acid. This is the main cause of loss capaciity in new batteries that sits on the shelf.
Our desulphation process and techniques soften up these sulphate molecules so that they can take part in the energy exchange again. In doing so it also exposes the active material below which results in the huge increase of capacity.
A new 12 volt 200 ah gel or agm battery can cost up to $2500. We sell these for less than $500. A small 400 ah 6 X 2volt cells can cost up to $8000 we sell these for $1200. Restored and recondition batteries although about 1/10 the price will last just as long ie 5 to 15 years.
Looking at it another way. For the price of a new battery bank, if you use restored batteries instead, you could pay for the whole system. The better news is that we can continue to support and service these batteries to extend their useful life.
Before setting up a system talk to us about your requirements. getting the correct batteries and keeping the path towards expanding your system open is the best way towards future proofing you considerable investment.
Feasible and Practical Solar Street Lighting
I was asked recently if it was possible to use solar power in street lighting. As always new developments in technology makes what was once not possible feasible. In this case developments in high intensity discharge and led bulbs that use less power and still provide equivalent luminousity as standard street lamps makes it feasible. However is it practical ?
Practicality
1. A 20 watt HID or LED lamp will require 200 watts hours (Wh) for 10 hours of lighting. So we need solar panel or panels that can produce more than 200 Wh a day. The next problem is to mount this panel or panels on pole we attach the street lamp to. Here the considerations of the height. strength of the pole and effects of wind sheer on the panels have to be taken into account.
2. On location where the panels are sited is vital to it’s effectiveness in producing power. If it is sheltered or shadowed these factors must be taken into account.
3. Next problem to solve is power storage. As sunlight is variable from day to day there will be days when power produced is less than the 200 Wh required. On these days we will have to depend on stored energy on days when we have excess to make up the slack.
4. A 40 ah battery stores about 500 Wh. If the worst day power production is 100 Wh this battery should provide enough for 5 days of uninterrupted lighting. Of course larger batteries will provide more uninterrupted days.
5. The problem with larger batteries is that they have to be mounted on the pole. A mid pole mount brings into question aestatics and wind sheer factors. In ground mount is not practical because of damp and flooding risks, An in pole mount is best but limits the size of batteries that can be used.
6. Instead of lead acid batteries we could use lithium ion. However a 40 ah 12 volt lithium ion battery would cost $1200 compared to a restored and reconditioned lead acid battery at $60.
So we see that what is feasible is not always practical. The ability to solve the practical problems is what divides those who succeed and the also ran.
Solar Power Water Feature
Most water feature used in landscape gardens uses 240 volt Ac converted to 12 volt Ac or DC. The modern landscape design should incorporate solar power to power Dc water pumps . Once installed it is completely self contained and the cost of running is zilch – nana – ZERO.
I have installed such a system in my garden. The first problem I encountered was that I could not get a Dc pump from the water feature supplier. Theirs was 12 volt or 24 volt AC and cost $150. I managed to obtained a similar capacity DC pump for $40 on the Internet. This worked perfectly on my water feature.
As I only needed the water feature to work in the day solar power was perfect as I had power for the water feature when the sun shone.
Full setup and details of this water feature design below
