Solar power
Solar Power Systems for your home – clean, green, renewable energy
What is a Solar Power(PV) system?
A Solar Power system (sometimes called photovoltaics, or PV for short) is a way of collecting energy from sunlight and converting it directly into electricity for use at home. Degree’s ‘on-grid’ PV systems also let you sell excess electricity back to your electricity retailer.
There is surging global demand for PV systems as production costs fall, electricity prices rise, and people become more concerned about the environment. Modern PV systems use advanced technology to produce zero-carbon electricity, and reduce users’ reliance on the national grid.
How do PV systems work?
PV Panels collect solar energy, and convert it directly into electricity. This electricity is then fed into and ‘inverter’ which changes the electricity from DC power to 240V AC power. This is the type of electricity that our homes run on. The electricity can now be used to run your home. If the electricity isn’t used immediately, it can be sold back to your electricity retailer.
This type of system is called an ‘on-grid’ or ‘grid-tied’ PV system.
What is an On-Grid system
Degree Ltd primarily quotes and installs on-grid PV systems. These systems are connected to the national grid, and do not typically use batteries for storage.
In contrast, and ‘off-grid PV system’ is not connected to the grid, and instead uses batteries to store excess electricity for later. They are more expensive to purchase and install, and maintenance is more complex.
How much does a PV system cost?
Most Wellington homes would suit a system sized between 1kW and 3kW. Prices vary depending on the size of the system, and design factors allowing for the pitch and direction of your roof.
Typically, you can expect to pay from eight thousand dollars to have a 2kW system installed. Degree Ltd will provide you with a full Project Plan (more on this later) including a detailed quote for all hardware and design factors.
What is the correct system size
It is important to match your PV system’s capacity to your household energy use patterns. Too large a system will produce surplus energy all the time but you’ll pay more in upfront costs; too small a system will cost less initially, but you’ll need to buy electricity when you could be generating your own.
To make sure you get the right system for your household, Degree Ltd will provide a report on your household’s energy usage data, and recommend the best sized system for your house.
Is PV a good investment?
A well-designed PV system will pay for itself in 10-15 years and keep on generating for at least another 20 years. This payback period assumes a current average electricity price of 26c/kWh. It also assumes that all the electricity generated by your PV system is used in the home when it is generated, rather than being sold back to your retailer.
If financial return is your key motivation for investing in PV, then the sizing of your system and your energy usage habits will need to be carefully analysed. You will want to sell as little electricity as possible back to your energy retailer and use as much of your PV power as possible in your home.
The reason for this is that while your retailer will sell you electricity for 26c/kWh, they will only buy electricity from you at a much lower rate (typically 6c – 17c/kWh). A system design that maximises the periods where you are using all the electricity generated will get you the best financial return, and keep your accountant happy. To help you work out the best return from your PV investment, Degree Ltd will provide you with a personalized PV investment analysis, on request.
