Most domestic solar power installations do not take you off the grid completely but rather augment your on-grid supply. Many people mistakenly believe that once the solar panel system is installed on the roof it will take care of saving you money for the foreseeable future without any input from you.
It is important to realize that the available power generated by your installation is not infinite. The usage of your solar power system needs to be managed, especially on cloudy days.
Before You Install A Solar Power System
1. Power conservation
Before you embark on a solar installation you need to be sure that your household is as energy efficient as possible. For example – install solar hot water heaters (if applicable), energy efficient refrigerators or other electric appliances. There are many older appliances that consume a large amount of power.
You have to work out a budget for yourself that takes many factors into consideration. Solar water heating is relatively cost-effective. Solar power generation is capital intensive and you need to look at your figures very carefully to decide whether it is the right route for you in your particular area.
Once You Have Installed A Solar Power System
Once you have a solar system installed you need to be aware of the following aspects of maintenance:
1. Cleaning Solar Panels
Due to the nature of the material the panels are manufactured from, they become electrostatically charged and actively attract dust. The slightest film of dust drastically reduces the efficiency of a panel. Panels need regular inspection and cleaning, especially during dry, dusty periods.
Panels are not damaged by the application of water. Use washing up liquid and water and the sort of non-abrasive squeegee one uses for vehicle windscreens or a soft mop or cloth. Make sure there is no grit on the cleaning equipment you use as this will scratch the surface and reduce the efficiency of the panel. Rinse off soapy water, rub dry and buff. For a particularly high-quality job you can use window cleaner for a final polishing.
2. Beware Of Over-loading!
If you are pulling more power than your installation can cover you are taking power from the grid and not really making much of a saving on power. If, however, you have an installation as a back-up system with batteries, it is important to be aware that the biggest expense of your installation is the batteries. You should also be aware that the length of the life of the batteries is entirely dependent on the discharge/recharge cycle. The more often you flatten the batteries, the shorter their life will be.
Your system was set up, in consultation with you, to run certain specific loads. Adding additional equipment not in that original calculation will have a detrimental effect on battery life (and can cause nuisance tripping of the inverter).
3. Load Management
Your system has been designed assuming that you will run larger loads in the middle of a sunny day – not at night or on cloudy days when you are drawing down on the batteries without the benefit of solar power. If you run heavy loads when the sun is not replenishing the charge you are in danger of overloading and detracting from the useful life of your batteries. (See Item 2)
4. Maintaining The Optimum Settings
Most inverters offer you a choice of settings. Not all set-ups are the same but what you find below are the general principles:
SOL (stands for “solar”) – the inverter will balance between the solar and on-grid power to keep the batteries charged and you will save money on your utility bills.
UTL (stands for “utilities”) – the inverter will prioritize using on-grid power over solar power for charging the batteries. This is a setting for cloudy days when the solar will be ineffective and will cost you money.
SBU (stands for Solar-Battery-Utility) prioritizes power from the solar power system to recharge batteries. If there is no solar (e.g. at night) it takes power from the batteries. When the battery power runs out it takes power from the on-grid system. The downside of this is that in a sudden power-outage situation you can find that your batteries are flat.
Ideally run on SOL and switch to UTL on a cloudy day and do not use SBU.
Make sure you are well-informed about the characteristics and options of your set-up when it is being installed. Have your installer talk you through your system and write down what to expect from the settings and the interpretation of the various readings that your system might offer, so that you can monitor the health of your system.
5. Corrosion Check
Regularly check all connections for signs of over-heating or corrosion.
6. Shade Check
Shadows cast by surrounding trees and foliage also greatly reduce efficiency. Watch out for encroaching tree growth and cut back where necessary.
Your Solar Power System needs TLC to keep it functioning efficiently. Set up a regular maintenance schedule and follow the tips above!