Looking to save energy in your property? Generating clean energy and reducing your fuel bills, we round up five different types of solar power panels you should invest in.
Image: Greenskies ST lifestyle flat plate system, from £3,000, Worcester Bosch
As a low-carbon, eco-friendly and renewable resource, one of the most powerful sources of energy is the sun. The most effective way to utilise the sun's energy is to install solar panels into your home but with so many different options available it can be difficult to know what solar panels are right for your property, and how cost-effective they really are.
We reveal the top 5 different types of solar panel and the benefits each will have on your finances and home.
Solar PV panels generate electricity to run appliances and lighting
Image: Rooftop six-panel PV 3kWp system, £4,550 including installation, Solarcentury at Ikea, ikea.solarcentury.com
Solar photovoltaic (PV) panels convert sunlight into electricity. They are made up of cells and their power is measured in kilowatts peak (kWp).
An inverter converts the power collected from a direct current to the alternating current that’s needed to run appliances. A solar battery can store excess electricity generated during the day, so it can be used when the amount produced is low. Costs vary, but the Energy Saving Trust estimates that a 4kWp domestic solar PV panel system will cost from £5000 to £8000.
Provided your system qualifies, you can earn money via the government’s Feed-in Tariff (FIT). The FIT is split into two payments – a fixed generation tariff, 3.93p per kWh, which earns you money from every kWh of electricity produced, and an export tariff, 5.03p per kWh, for excess units exported back to the National Grid. To qualify for the best FIT rate, your home must achieve an Energy Performance Certificate rating of D or above and the system and installer must be approved by the Microgeneration Certification Scheme.
Solar Thermal Systems produce hot water, reduce energy bills and lower carbon footprint
Image: This Solar PV 5.34kWp system integrates seamlessly with the curved wooden roof panels. Price on application, EvoEnergy
Solar Thermal Systems use the sun’s warmth to heat water, which is stored in a twin coil hot water cylinder. There are two types to choose from: flat plate, which is cheaper, or evacuated tube, which is more efficient. The Energy Saving Trust recommends installing about one square metre panel per person and a well-specified system delivers around 60% of a family’s annual hot water requirement. You’ll need a boiler or heat pump for heating and to provide hot water when the system isn’t producing enough during winter months.
Solar water heating qualifies for the Renewable Heat Incentive (RHI), a government scheme that pays householders for generating heat using renewable energy. Properties need to meet minimum efficiency standards and the current rate is 20.06p per kWh.
‘While solar thermal isn’t as popular in the UK as it was, and it often loses the battle for roof space with solar PV, the technology is well subsidised by the RHI. We’d strongly advise anyone installing a heating system to make it solar thermal compatible, if not for now, then for the future,’ says Darren McMahon, marketing director at Viessmann.
Integrated solar panels are an energy efficient option for listed buildings or conservation areas
Image: Flat-plat ST system with ThermoProtect, from £4,000, Viessmann
New technology is bringing integrated panels and tiles to self-builders and renovators who want to incorporate solar PV or ST systems into the fabric of their roof.
‘Integrated solar panels are fixed above roofing membrane and battens, replacing the tiles for a sleek, low profile,’ says Stuart Elmes of Viridian Solar. Solar slate roof tiles are unobtrusive, improve energy efficiency and are an option for listed buildings and conservation areas.
The experts at Viridian Solar also explain the benefits of opting for above-roof solar PV over roof-integrated solar PV. 'Above-roof systems will operate at a lower temperature due to better ventilation. Since soar PV power output falls as panel temperature rises the argument goes that roof integrated solar will have a lower energy yield.
Viridian Solar and researchers from the University of Cambridge have examined this effect. The published research found that the reduction in energy yield was very small, of order only 3%.'
Evacuated tube solar thermal systems are the most efficient with conservation energy
Image: Greenonetec ST system with panels around 4sqm, from £4,000, Norfolk Solar
A solar array doesn’t need to be mounted on the roof but it does need to be as south-facing as possible, and set on an incline close to 30 degrees, otherwise performance drops off. Evacuated tube solar thermal systems are slightly more tolerant to being other than south-facing, but to work effectively all panels need to be free from any shadows cast by surrounding trees and buildings, plus PV panels need more roof space.
The UK's premier energy saving advice portal, The Green Age, describes how 'solar thermal harness the sun's energy by turning the solar radiation into heat which is usually used for water.'
They go on to advise that a 'typical evacuated tube solar collector system will cost about £3,000 – £5,000 to get installed on your property, and will typically produce about 1,000 – 2,500 kWh of useful heat – or about 50% of your hot water requirements. As long as you get it installed by a MCS approved installer you will then be entitled to the renewable heat premium payment grant which for solar thermal installations is about £600.'
Photovoltalic Thermal Systems yield hot water and electricity to produce renewable low-cost energy
Image: Passivhaus with Clearline Fusion solar PV, from £6,000 for a 4.3Wp system, Viridian Solar
A photovoltaic Thermal System (PVT) yields hot water and electricity from the same panel. Systems don’t benefit from the FIT or RHI incentive schemes, so PVT is for people who want to reduce running costs by producing as much renewable low-cost energy as they can.
New innovations allow hybrid panels to use wasted heat from electricity generation and convert it to energy for hot water.
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