FAQs for Solar thermal and Solar PV installations

Do Solar Panels Work well in the UK?

It is a mistaken notion that we do not receive sufficient solar energy in the UK! Compared to the equator, the UK receives approximately 55% of the energy received there, ample to operate an efficient solar water heating system, even in the North of Scotland. Optimum performance will be gained with a south-facing roof.

How much conventional energy will I save? 
 55% to 70% of the energy required to heat your hot water.

What size of Solar thermal system do I need? 
When using an efficient solar collector you need around 1 square metre per 60 litre hot water cylinder capacity.

How do I size my hot water cylinder? 
40 to 60 litres per household occupant.

What temperatures can I expect from my solar thermal system? 
On sunny days temperatures of 70 deg C to 85 deg C are common.

Can my cylinder be placed above the panel? 
Yes, as long as the mains hot water supply is not affected.

Do I get hot water during the winter months? 
Even during cloudy days in winter you can expect some gain. On sunny days, 10 to 15 days per winter month, you can get water above 45 to 50 deg C.

What is the Science of Solar Panel Technology?
Quite simply when solar radiation enters the earth's atmosphere it does so as a short-wave. When these short waves hit something, be it a person, building, or solar panels, the short waves will then convert to a long wave. This process expels energy and this energy produces heat.

What are the Principals of a Household Solar Hot Water Heating System?

A household solar water heating system uses solar collectors to capture solar energy and uses such energy to heat water for household use. A cylinder is used to circulate the cold water supply and then in turn store the heated (circulated) water available to drain off as required.

How Long Will My Solar Panels Last?
Most manufacturers offer guarantees of 20 years with expected life span of 30 + years.
Which Solar Collector do I use?
There are two main categories of solar collectors in the UK, these are flat plate collectors & evacuated tube collectors.
Both of the above are highly efficient with the evacuated tubes having a slightly higher efficiency for a smaller square meterage, however many people prefer the appearance of flat plate collectors.
Our 'FREE' home survey will help to determine your individual home requirements.

Do I Need Planning Permission?
In many cases, planning permission is not required if solar panels are fixed to the roof of a single dwelling house.
The following apply to roof and wall mounted solar panels:-

•Panels should not be installed above the ridge line and should project no more than 200mm from the roof or wall surface.
•If your property is a Listed Building, installation is likely to require an application for listed building consent, even where planning permission is not needed.
•If your property is in a Conservation Area or in a World Heritage Site, planning consent is required when panels are to be fitted on the principal or side elevation walls and they are visible form the highway. If panels are to be fitted to a building in your garden or grounds, they should not be visible from the highway.
All solar installations are also subject to the following:-
•Panels on a building should be sited to minimise the effect on the appearance of the building.
•Where they are no longer required for microgeneration, they should be removed as soon as possible

What is the Feed-in Tariff?
The feed-in tariff is a government scheme that rewards homeowners for any renewable electricity they produce. The Feed in Tariff pays 41.3p/kWh for a system up to 4kW in size.
Do solar cells store energy?
Solar cells just convert sunlight into an electric current that must be used immediately . In grid-tied solar systems, the utility company essentially acts as your home battery in that your excess power if fed back into the grid during daylight hours with your electrical meter running backwards. At night, you draw back what you need
How well do solar panels work in the winter?
Solar panels work on light not heat and actually work best when cold. However, with shorter daylight hours in winter, solar panels produce proportionately less power than say the longer summer days. If there is a wet snow and the solar modules become covered, they stop producing power, but snow generally melts quickly when the sun strikes the modules; if you brush the snow off, they resume operation immediately.
Are Solar pv systems safe?
Solar cells are mostly silicon, the primary component of sand. There is no exhaust and no toxic materials to leak out of the system. The electricity coming through the inverter is just like the electricity coming from household wall sockets; you should use the same care you would with utility power. All components are approved for utility interconnection and are installed according to standard construction practices.
How much electricity does a PV system output?
For every kW peak power installed on a South facing roof the system will generate around 800 kWh. This reduces by around 20% for an East or West facing roof.
Are your panels approved?
We only use the very highest quality of materials. The panels we use meet all the required standards including TUV and MCS approval for government incentives.
What is the difference between monocrystalline and polycrystalline PV panels?
Monocrystalline panels tend to be slightly more expensive than polycrystalline panels, however monocrystalline panels are regarded as having a higher output per kW peak power installed. Polycrystalline wafer has a dark blue colour, monocrystalline wafer is black.
What is a kWh?
A kWh (pronounced ‘kilo watt hour’) is a specific amount of electricity. 1 Kwh is identical to 1 unit of electricity that is shown on your electricity bill. An electrical item having a rating of 1kW will consume 1kWh for every hour it is on at full power.
What does the inverter do?
The PV panels generate direct current (DC), this is not directly compatible with the 240V alternating current (AC) that is used in your property. The inverter converts the DC power to AC power that can be used in your property.