How much do solar panels cost and are they worth buying as a home improvement? Solar panels can be expensive, but the money you save on electricity bills will pay for the system in seven years or less and that is in places where solar power is more expensive to buy. A five year payback period is not uncommon, but even if it takes seven years, you will continue to save money after the payback period.
- What is solar power and why should you consider it?
- How much does solar power cost?
- How to get the right sized solar system
- Why investing in a solar system battery is a good idea
- Choosing a solar panel supplier and installer
What is solar power and why should you consider it?
Solar power systems are also called solar photovoltaic (PV) systems. They work by collecting solar energy in solar panels which are normally roof-mounted, but can be mounted on the ground. The solar energy collected is converted into alternate current (AC) with an inverter. While solar panels will only work during the daytime, battery storage units are available that allow the excess power to be used at night.
Solar power has been through three stages. Until about 2011, solar panels were expensive and the payback period was longer. After 2011, they started coming down in price and today, the price of solar panels has stabilised and is far more affordable than in the past.
Solar panels have also improved in efficiency and reliability. In the past, solar panels were expensive and most homeowners bought smaller systems up to 2kW. Today, a 5kW system is about the same price as a 2kW system was before 2011 and is a better system to have because it can account for most if not all of your energy requirements.
How to get the right sized solar system
Solar panel systems are made up of several panels and the size of the system is based on the number of panels and the efficiency of the panels. Estimates vary because solar panels can be installed in areas where the sun rarely shines or in sunny areas. Solar panels can also be installed on roofs that have partial shade during the day, which decreases their efficiency. These are averages and your solar power installer can tell you how efficient your solar power will be in your area.
Solar power is measured in “self-consumption” which is an indication of how much energy you use during the day. These are some estimates of how much energy you will save for different energy consumption levels with a 5kW to 10kW system measured in kilowatt hours (KWh):
- 5-10KWh will save 30 percent
- 11-15KWh will save 48 percent
- 21-25KWh will save 66 oercent
- 31-40KWh will save up to 82 percent
It is possible to get a solar system that is too large for your household, but you don’t want to get a system that is too small for your household. Solar power retailers and installers can help you find the perfect system for your needs and a smaller system for a smaller household will cost less than a larger system.
Why investing in a solar system battery is a good idea
The prices above are for solar panels only and a battery will cost more. A battery is a good investment because you are likely to be able to store energy in the battery during the day and have it to use at night. This will decrease your use of electricity from the grid and lower your electricity bills.
Solar batteries are a good choice, but you don’t want to buy a solar battery that is too small or too large for your solar panels. Sizing of batteries is based on average electricity usage and the size of the solar system you have. Batteries don’t just store enough energy to keep your house powered overnight. If you get the right sized battery it can give you “energy autonomy” for three to five days.
Solar batteries cost between R20000 and R120,000, with the higher cost being batteries for large systems and a large battery can weigh up to 290kg while a smaller battery may weigh only 25 to 45kg. Even at the higher end of the scale, batteries have a payback period of three to five years and their warranties are far longer than their payback periods. Better batteries have a 10 year warranty and others may have a seven year warranty. Even at seven years, you still save money since the payback period is five years maximum.
It’s probably a good idea to buy lithium batteries because lithium batteries generally have 10 year warranties and are highly effective. They aren’t hard to find because about 80 percent of solar batteries on the market are lithium batteries.
Batteries with inverters and chargers can be more expensive than batteries only. A battery for an 8kW system may cost around R77000 while the same sized battery with an inverter/charger may cost around R110,800. These prices include the battery and installation costs. Most households don’t require an 8kW system, but this is an indication of the price differences. The key thing also to remember is to know how to keep solar panels clean to make them last.
Choosing a solar panel supplier and installer
Finding a certified solar panel supplier is fairly easy because most solar panel suppliers are certified. However, they also sell different products and you want to find good solar panels and batteries with long warranty periods.
Compare the prices carefully and choose a high quality system at the right price. Some other things to look for are:
- Solar installers must be licensed
- They should be fully insured
- They should give you itemised quotes
- Their warranty periods should be stated
- Their products must meet South African Standards
Also ask about the efficiency of the systems they sell and if they offer an installation warranty. Better solar suppliers and installers will be able to give you references you can contact to find out about their service.