What solar PV is and why it is good
for your home?
Solar Photovoltaic Systems works by generating electricity from panels (typically 14 or 16) on a roof or ground mount frame from DC power to AC Power which is done by the use of a Solar PV Inverter. The PV cells convert the sunlight into electricity, which can be used to run household appliances, heating and lighting. The average domestic system running on single phase electricity is 4kw peak and this is usually made up of 14 x 305-Watt Modules (1.7m High x 1m Wide), which come in all black frame to suit the roof type.
An average system fitted on a South Facing roof will generate 3,300 kwh of electricity per annum. If all of this is used in the home this would save £594.00 each year (based on electricity price of £0.18p/kwh after VAT is included) on the annual electricity bill.
Simple Payback
Based on a 4kw System installation cost of £5,700.00, the payback assuming all of the energy created by the PV array is used in the home would be 9.59 years. If a customer is using 60% of what the system generates the simple payback would be 16 years. The key is to stagger the use of domestic appliances throughout the day and run them when the solar gain is at its maximum. (In summer this is usually 11am to 5pm).
System Life Expectancy
The expected lifetime of the PV Panels is 25 years and the inverters we install have a 10-year warranty. The PV Panels have a 12-year manufacturer’s warranty. The system is pretty much maintenance free similar to any other domestic electrical circuit.
Maximising System Production
With the Ecoforest E Manager, we can design a system that will enable your Solar PV to communicate and manage the operation of your geothermal or air source heat pump, therefore using all the usable free electricity generated to heat your home and hot water.
A further way to maximise use of the power generated by the PV System, is to consider devices such as the Solar I Boost and Zappi car charger, which can be added to the system to bring self-consumption closer to the 100% mark. A Solar I Boost will divert any excess power that is generated into the 3kw immersion in your hot water tank to help heat the hot water used in your kitchen and bathrooms. The Zappi car charger will divert excess power into your electric car to charge it for free if it is left plugged in during daylight hours.
It is more beneficial to try to use as much power as possible in the home as the power providers only pay a nominal rate of 4p/kwh. Having a heat pump providing heating and hot water will also help to reduce the running cost of the heating system by approximately 20% which could equate to a saving of £100.00 per annum.
The complete system design (including wind and snow loading report), installation and commissioning is undertaken by Daly Renewables. Upon system testing and final commissioning Daly Renewables will submit a ‘G98’ application form to NIE Networks in advance of NIE visiting site to exchange the existing house meter to an import/ export meter.
Solar Water Heating
Solar Water Heating, also known as Solar Thermal, can take the form of 2 types of panels:
- Evacuated Tubes
- Flat Plates
Solar Thermal provides up to 60% of a typical Ireland or UK’s household’s hot water needs and is a good renewable energy solution in houses where there is a higher than normal hot water requirement. We use Veissman products, designing bespoke solar systems to suit site location and installation considerations. Solar panels are at their maximum efficiency when they are mounted on unobstructed south facing roofs at an angle of 30-50 degrees.
On a typical south facing roof with a 40o pitch, a 5m2 solar system will generate approximately 2,000kwh of energy per annum. The sizing of a solar system is critical to the long term performance of the system as oversizing the collectors could lead to stagnation issues in the summer months and cause long term damage to the system. Some examples of where solar thermal is an excellent option include:
- Families that have a big hot water demand – teenage children showering for example.
- Houses that do not have enough space to accommodate a PV system but still would like to reduce their energy costs.
- Sports clubs, hotels, restaurants and similar types of entities which have a high hot water demand.
We use Veismann solar thermal panels. Click here to view their brochure.
For more information on on Solar PV or Solar Thermal just contact us and we will provide you with professional advice on the merits of installing this technology.
Does your family consume more electricity in the evenings? We recommend our Solar PV battery storage solution
