What is SOLAR Power?

SOLAR Power is the useful energy that can be harnessed from the sun's radiation. Even when the sky is overcast, using the latest technology, daylight can be converted into hot water or electricity which we all use and possibly take for granted in our homes every day. If you would like some fact sheets about SOLAR Power, contact us.

Why do we need SOLAR Power?

The sun has heated the earth ever since time began and it is the very essence of life as we know it. Over millions of years plants have evolved and produced oxygen which has supported the development of all forms of life on earth. However the last two hundred years has seen some major industrial and technological development. The industrial revolution, which evolved here in Great Britain, developed mechanisation of the way work was done and has changed the human social history of the world. The use of fossil fuels was at the heart of this industrial development which is still going on today in places like China. Unfortunately the combustion of fossil fuels like coal, oil and gas to produce power and electricity and for transport has also produced significant levels of pollution. Harmful gases like Carbon Dioxide (CO2) have been released into the earth's atmosphere forming a shield trapping the heat from the sun and causing global warming. This has changed the climate on Earth causing extreme weather patterns with some countries reverting to a state of desert whilst others have been subjected to severe storms and flooding. It is also thought that this warming is melting the ice at the north and south poles which could cause sea levels to rise and increase flooding. This could also reduce the salt content of the sea which could affect the way in which the gulf stream works warming our northern European climate. It is thought that if the gulf stream shuts off we could experience another ice age within a few decades. These thoughts are controversial but have a lot of scientific evidence supporting them.

If you have any comment about this please, contact us.

Here in the UK on average we receive about 60% of the SOLAR radiation received at the Equator. Our Thames Valley region receives an average of about 1100 kilowatt hours of SOLAR energy for every square metre of sloping roof (at 30 degrees) every year. Nationally this SOLAR radiation is equivalent to the output of 1000 power stations. The average property requires 3000 kilowatt hours every year for domestic water heating alone. Taking into account the efficiencies of the different types of SOLAR collector a SOLAR Powered system could save up to half of the domestic hot water heating costs every year. (Source: the Solar Trade Association).

Using clean renewable SOLAR energy like this would reduce the need to use coal, oil, gas and electricity fuels together with the associated pollution. It would also reduce our energy bills and the dependency on unpredictable future fossil fuel supplies.

For more detailed information about this subject please use our links page to access the many excellent official web sites

How can SOLAR Power be used?

Solar Thermal Panels can convert daylight into heat energy and Photo-Voltaic panels can convert daylight into electricity which we can either use directly or feed into our national power grid. The sun does not have to be shining but when it is, more energy is produced. SOLAR energy is also stored in the Earth itself, in the air that we are surrounded with and in the buildings that we design and construct. We can tap into these sources of stored SOLAR energy by using Heat Pump Technology to convert the stored energy into heat energy for our homes.

Isn't a SOLAR Powered system expensive?

Technology has improved with prices reducing significantly in recent years. With fuel prices rising and future supplies becoming unpredictable, modern SOLAR Powered Systems are very good value for money. Why not get the facts, have our no obligation FREE home energy survey and report and quotation, then decide for yourself if it is worth harnessing the FREE energy from the sun to help reduce your future water heating costs and electricity bills. (Source: Solar Trade Association).

What about Grants and Tariffs?

The new Feed-in Tariffs (effective from April 1st 2010) replace the Low Carbon Building Programme Grant scheme for Solar Photo Voltaic systems. As well as reducing your electricity bill by using your own electricity during the daytime, you can receive a Generation Tariff of 41.3 pence per kilowatt hour generated and an Export Tariff of an extra 3 pence per kilowatt hour for any surplus electricity that is not used and exported out to the national grid for others to use. These Feed-in Tariffs are tax free, index linked and guaranteed for twenty five years.

A similar scheme for Solar Thermal (including Heat Pumps, Biomass boilers etc.) called the Renewable Heat Incentive is under consultation and due to be introduced in April 2011.

Isn't the payback period too long?

The latest equipment is extremely reliable and efficient at making the most of our European climate. Even assuming moderate increases in traditional fuel prices a good SOLAR Powered system will easily pay for itself during its lifetime (possibly many times over depending upon your circumstances and hot water or electricity usage). How many household purchases can you say that about? Also the capital cost of the system would certainly increase the value of the property. The new Feed-in Tariffs for self generated electricity could reduce the payback period to as little as ten to fifteen years. The alternative is to continue to give the money to the energy providers year after year and have nothing to show for it. Which would you really prefer to do?

If you would like a realistic estimated pay back period for your circumstances why not have our FREE home energy survey and report.

SOLAR Power doesn't really work in this country does it?

We have heard this old chestnut for over 25 years and have concluded that it is an excuse used by some people who have decided that global warming is a myth and that they are determined not to do anything about reducing CO2 emissions. Do greenhouses get hot??? Do south facing conservatories get hot??? When you park your car facing the sun does the bonnet sometimes get too hot to touch???

If you really want to know if it works just talk to someone who has got it!

To find out if SOLAR Power can work for you, get our fact sheets and have our FREE home energy survey and report.

How hot will my water get?

Your domestic hot water cylinder thermostat should be set at 60 degrees C. A good SOLAR system should easily achieve this on most days between April and October. If your consumption of hot water is very high or on extremely overcast days your boiler may need to be used to help supplement the SOLAR system and ensure that the cylinder is heated to 60 degrees C every day. During the winter period a SOLAR Powered system will still work but your boiler will need to be used to maintain good supplies of hot water and heating.

It is also important for hygiene to heat your domestic hot water cylinder to 60 degrees for at least an hour every day.

How much electricity can I produce?

This will depend upon a number of factors such as: Orientation towards south; Pitch of roof; Size of available roof space; Shading from trees and other buildings and of course the size and quality of solar collector equipment used. If you would like a no obligation quotation (or range of quotations) of performance and accredited installation cost then please contact us.

Can SOLAR Power run my central heating?

Most traditional heating systems will need a boiler to provide the power required in winter months and SOLAR Thermal collectors will not be able to achieve this high level of power at this time of year. However a 'thermal hot water store' is designed to receive inputs from various power sources including a boiler, SOLAR collectors, heat stoves (Aga or Rayburn cookers etc.), electric immersion heater. The 'thermal store' will use its stored heat to supply your domestic hot water (at mains pressure if required) and can supply under floor heating systems which could be incorporated into new buildings or extensions etc. In this instance the SOLAR system will help the boiler to do its job and save energy. Heat pumps which draw their source of heat from the air or just a few feet below the ground level can also be considered to be producing SOLAR power and are capable of providing sufficient power to heat domestic hot water or for under floor space heating. Biomass boilers use wood pellets or logs harvested from recent origin. These are not considered to be fossil fuels because these trees will absorb CO2 when growing and release the CO2 when combusted in a boiler. They are therefore considered to be 'carbon neutral'. When your existing boiler needs replacing perhaps you could consider these alternatives.

If you require more information about this, contact us.

Will SOLAR Power work with my combi boiler?

Most combination boilers made before 2007 are intended to heat water directly from the cold mains supply and are not designed to receive pre-heated water from SOLAR or any other source. However most boiler manufacturers now realize the benefits of using SOLAR Power to pre-heat the water therefore helping the boiler to save energy and have started to make a new generation of SOLAR compatible boilers. When the time comes to change your boiler you might consider the benefits of this or alternatively investigate the combination of a heat pump together with a thermal store as described previously.

Will it freeze in winter?

We use a special SOLAR fluid which will tolerate extremes of temperatures above minus 24 degrees C.

Do I need planning permission?

For most houses outside conservation areas a SOLAR Powered installation would be considered as normal permitted development subject to certain conditions. You can enquire with your Local Planning Authority regarding your available permitted development rights. It may be possible to install a SOLAR system within a conservation area or on a listed building but this would usually require a full planning application to be submitted to the local planning authority for their consideration of the individual circumstances. If you would like further guidance regarding planning please contact us.

Will it require maintenance?

Every five years the solar thermal collector panel should be cleaned and the system drained, flushed and checked. Any faulty components should be replaced prior to new fluid being installed and the system re commissioned. This is a chargeable service but should ensure your system to be fully functioning for another five years of good service and energy savings. Photovoltaic systems do not have any moving parts so there is little to go wrong and there is no regular maintenance required apart from occasional cleaning of the glazed collector panel.

Which collector: Flat plate or evacuated tube?

First of all it has to be said that they both work but in different ways from each other.

Flat plate collectors were first developed about a hundred years ago and very simply are an insulated box with a glazed front panel which allows the radiation through onto an absorber plate. This plate is connected to a tube which passes on the heat to the solar fluid passing through it on its way down to the coil in your hot water cylinder where it heats your domestic hot water.

There are some very interesting design variations of flat panels available on the market today.

Evacuated tubes were developed in the 1980's. Most make use of a strong (borosilicate) glass tube (similar to pyrex) which allows the radiation through onto an absorber plate or pipe running down inside the tube. Incidental radiation can be reflected from underneath the tube back onto the absorber by a reflector. A vacuum is created and sealed between the glass tube and the absorber pipe which acts as a good insulator against heat loss from the absorber pipe. A series of these tubes are connected to a top manifold which contains the solar fluid. The premium quality British Thermomax brand uses low iron solar glass with an extremely high light transmission value.

There are basically two types of evacuated tube collectors:

In the first type the solar fluid flows directly from the top manifold down through the absorber pipe and back up to the manifold again collecting heat on the way, then on to the next tube and then down to heat the water in your hot water cyclinder.

The second type is very clever and is called a heat pipe. The absorber pipe is the heat pipe and is sealed containing a special fluid. This vapourizes when heated and is conducted up the heatpipe to the manifold end where it condenses. This releases the heat through the condenser end of the heat pipe to the solar fluid passing through the manifold. This award winning technology works really well and was developed commercially here in the UK over 25 years ago. Thermomax have patented a temperature limiting valve for their heat pipe collectors which prevents the collector from over heating.

Flat panels do not perform as well as evacuated tubes in cold or windy situations and are generally not as efficient but usually cost less. Because our climate and individual circumstance are not always ideally suitable conditions for maximizing the use of SOLAR Power we recommend that you consider the most efficient system that you can afford within your budget.

If you would like some information about the different collectors and which might be best for you, please contact us.

So how does it all work then?

Solar thermal systems heat your domestic hot water in a cylinder (in the airing cupboard) with cold water tanks in the loft then very simply the heated solar fluid is pumped from the collector down through a coil of pipework inside your domestic hot water cylinder where the heat is transferred. This is similar to the way your boiler heats your domestic hot water but if the SOLAR system has already heated it the boiler needn't switch on, therefore saving fuel. The cooler solar fluid is then pumped back up to the collector for re-heating. This cycle continues until your domestic hot water is at the right temperature (60 degrees C) when a temperature sensor switches the pump off. If you then use some hot water, say for a bath, the sensors on the system switch on the pump and draw more heated solar fluid down to reheat your hot cylinder again. All designed to save using your boiler or immersion heater which will reduce your fuel bills and future dependency on the traditional coal, oil and gas fossil fuels.
There are different systems for heating domestic hot water and SOLAR Power is not always compatible.

Solar photovoltaic system collectors produce low voltage electricity (Direct Current). This is then inverted to full mains electricity (Alternating Current) and is connected to the mains distribution board for use within the household. If you can arrange to use your electrical appliances during daylight hours when you are generating your own electricity you will save having to buy in some electricity thereby reducing your electricity bill. In addition to this saving you will receive a Generation Tariff of 41.3 pence for every kilowatt hour of electricity that your system generates, whether you use it or not. Any surplus electricity will automatically be exported out to the national grid for others to use and you will receive an additional Export Tariff of 3 pence per kilowatt hour for this.
To find out if SOLAR Power could work for you, get our fact sheets and have our FREE home energy survey and report.

OK, I am interested. How much does a SOLAR system cost?

This is one question we would really like to get right for you. As you have probably gathered by now SOLAR Power does not work for everyone's situation and there are so many questions that need answering regarding your individual circumstances:

- Is my domestic system suitable for SOLAR?
- Which type and how many collectors would be required?
- Is my roof suitable and facing the right direction?
- Would I require a new hot water cylinder or boiler?
- How much would my fuel bills be reduced by?
- How long will it take to get my money back?
- Do I need planning permission?

Our FREE home energy survey and report will answer these questions and any others you may have and if we establish that SOLAR can work for you we offer you accurate quotations for the most suitable types of system for your circumstances.

Then it's up to you!

If you have any other questions or would like some more information then please do not hesitate to contact us.

We are members and abide by the strict code of ethical conduct and practice of the Solar Trade Association.