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Frequently Asked Questions - General

1. If you had to put in one sentence what buying a Solar PV or Thermal Energy System would do, what would you write?

2. Apart from saving money what are the mains reasons why I should buy a Solar Energy System, what would it be?

3. What do Solar PV and Thermal Systems do?

4. What sort of Return on Investment will I get?

5. How much have energy prices risen?

6. What are future energy bills going to cost me in?

7. Who pays for a Solar System?

8. When will I get Free Energy?

9. Do PV and Thermal Systems depreciate?

10. How do PV and Thermal work?

11. Does Britain receive enough energy to make these systems work?

12. Do they require direct sunshine to work?

13. Do the PV and Thermal Panels have to point South?

14. Can shading decrease the power output?

15. Is Planning permission required?

16. Is Building Control Permission Required?

17. Do we have to Clean the PV panels or Thermal Collectors?

1) If you had to put in one sentence what buying a Solar PV or Thermal Energy System would do, what would you write?


We would probably say that a Solar Power Station, whether PV or Thermal, converts free Solar Energy into power, paying for itself with money you would only be going to pay your Energy Supplier, and once the savings equal the cost you get free power forever, whilst helping to save the Planet.



2) Apart from saving money what are the mains reasons why I should buy a Solar Energy System, what would it be?


If you have seen the Film by Al Gore, An Inconvenient Truth, or just listened to the news, day after day, Global Warming is the biggest danger all of us face. The CO2 level in the atmosphere was 280ppm in 1780 and now is 382ppm. Up to the year 2000, it was rising at less than a 1% increase per year, but since then, has been rising at over 3% a year. The CO2 level is rising because we are burning fossil fuel, and although it isn’t the only dangerous gas, it is the most important.


If we do not stop this continuing, and CO2 levels rise even faster, there will be a climatic disaster, affecting every one of us, and more importantly, the future generations. Our children, and grandchildren, will be greatly affected by what we do or don’t do. Solar Power Stations stop the emission of many tons of CO2 during their lifetime, even small domestic Systems, so buying one will help prevent global warming.



Apart from saving money and the environment, there is another good reason for seeking alternative energy sources. Solar, Wind and Nuclear will only give electricity, however by products of crude oil is omnipresent and cannot be easily replaced. Examples of the by products are tarmac, plastic, pesticides to name a few. This is a good reason why we should preserve the reserves of crude oil and seek alternate sources for power generation.


3) What do Solar PV and Thermal Systems do?


Solar Thermal Systems - These Heat Water and are used to provide up to 70% of your domestic Hot Water requirements, and is ideal for under floor space heating. They can be used to heat indoor, and outdoor swimming pools, and can provide Hot Water and heat swimming pools at the same time. For indoor pools up to 70% of the energy can be provided and for outside pools, used in summer only this can be 100% of the energy required.


Solar PV (photovoltaic) Systems – These produce Electricity and Government Grants pay for up to £2500 of the cost. The amount of Electricity produced, is directly related to the number of Solar Panels installed. If you use under 5000 Units of Electricity, and have a sufficient space to place the PV Panels on your property, all your Electricity needs may be met, so you can have Free Electricity for life. Indeed, some people install PV Systems that produces more energy than they use, and make a profit from selling it to their Energy Supplier


4) What sort of Return on Investment will I get?


A very good article was written by Ashley Seager for the Guardian, on September 11th 2006, stating the current rates of return on PV and Thermal Systems. For PV there was about a 5% Return On Capital Employed, due to the Saving on the Energy produced, Monies back from the Suppliers for the Energy sold to them and for the £30 a Kilowatt received from the sale of Renewable Obligations Certificates (ROC’s). On Solar Thermal, a return of 4.25% was calculated for mains Gas, and 8% for other Fuels.


His concluding sentence was: - So why wait? The returns already justify the outlay and, if you are worried about Global Warming this is a concrete step you can take with tried and tested technology. Just do it.


We could not put it better ourselves, and this is at Today’s price of Energy. How much more will it save in the Future.


5) How much have energy prices risen?


Energy bills have risen steadily and from 1974 to 1999 Gas prices rose 411% and Electricity 717%. From then until 2003 they were rising at over 14% per annum.


From Jan 2003 to Nov 2006 Gas rose by 97%, an increase of over 20% a year. Electricity prices have risen by 60% from Jan 2003 to Nov 2006.


We all know that even if wholesale price of Gas comes down, it will not be reflected in lower prices. The Carbon Offset Tax for each EU Country, and the need to invest in the infrastructure, ensures Energy prices are only going up.


6) What are future energy bills going to cost me in?


That we don’t know but prices rise as in compound interest, by percentage loaded onto percentage so if prices only rose 10% a year :-

Today’s bill  £950

Year 5      £1550

Year 10 £2450

Year 15 £3950

Year 20 £6400


Over 20 years the total you will have paid is £61,000


If the % rise stays at much higher levels than above, the money you may pay out over 20 years could be double the £61,000, or worse. So how does that make the investment seem now? Pretty good we would have thought.


7) Who pays for a Solar System ?


Once a System is installed, you immediately start saving the Money you would normally be paying your Energy Supplier, and for PV the extra income from ROC’s, so in effect it is your Energy Supplier who is paying for your System. If you do not purchase a System, you just carry on paying their bills, and are left with nothing whatsoever, to show for your money.


8) When will I get Free Energy?


Once the money you would have given your Energy Supplier is equal to the price of the Solar System you bought then all the Energy you generate is Totally Free.

General Questions

General Questions

9) Do PV and Thermal Systems depreciate ?


Not for a very long time - As if just saving money is not good enough, PV and Thermal Systems will retain their Value for many Years, so if you sell up you can add the price you paid for the Solar System to your House price, or if not just take it with you. PV systems are very easy to move, and it is not that difficult to move Thermal, although you would leave the Solar Hot Water Cylinder.


Just compare that to a the value of a Car for the same money. A Thermal System costs about the same as a 6 years old runabout, which, when 10 years old, is worthless. The same Car, when new, may cost a similar amount to the biggest PV system available, yet worth only 30% after 6 Years, and worthless after 10, when we expect the PV or Thermal Systems to be worth about what you paid initially.


10) How do PV and Thermal work?


Both PV and Thermal work by absorbing light, plus Infrared and ultraviolet radiation, which they convert into energy we can use. Each works in a different way, the end result being Heated Water for Solar Thermal, or Electricity for PV, and many people have both installed at the same time. They are not interchangeable, although a PV System can power an immersion heater to heat water, but that isn’t the best use for it.


11) Does Britain receive enough energy to make these systems work? 


The answer is yes. We receive about 60% of the radiation that lands on the equator, and although there is a variance between the North of Scotland and the South West, there is more than enough energy to power Solar Energy Systems. In the South of England each year, we get about 1300 Kilowatt Hours of energy striking every square metre of the ground, or roof


Approx 70% of all energy falls between March to September, with the remaining 30% from October to February


12) Do they require direct sunshine to work?


No - Diffuse light, through cloud, is fine, which is prevalent in Britain.


Indeed, the Solar Thermal Vacuum Tube Systems can work in temperatures as low as - 30C, and even in mid-winter, on a cloudy day, the water in the Collectors can reach 30/40 degrees C.


The PV Systems work all the year as well, although producing less power in winter. However, PV Systems often produce more power in summer than is usually used by a household, even on some of the smaller Systems, so the excess Energy is sold to the Energy Supplier. Obviously, strong direct sun does increase the output, so the more sunshine we get, the more power the Systems produce, and this year there has been higher outputs than ever before.


13) Do the PV and Thermal Panels have to point South?


No – Actually, the most energy gain is to be had from tracking the sun daily, so the Panels would rotate from North East to North West at 10 degrees pitch in June, and South East to South West at 50 degrees pitch, in December. However, although there are systems for PV doing just that, for practical purposes almost all PV and Thermal Panels are fixed in a stationary position.


For fixed Panels, facing South tilted at 30/40 degrees is the best compromise, but you only lose 4% of available power if the Panels face between South East and South West, and 86% if placed facing due East or West. Even if you laid a Panel flat, you would still get 90% of the total power available,


If a roof has a North/South ridge, we place half the Panels on the East side, and half on the West, which gets over 90% of the total again. Panels placed in these positions start power production earlier, and continue later, than South facing Panels. Panels can also be placed in arrays, in Gardens, or on outbuildings or sheds.


14) Can shading decrease the power output?


Yes - Trees or buildings casting shadows on the Panels (particularly PV) can decrease power outputs. However, when the sun is strongest in summer, the sun is very high in the sky and rarely casts much of a shadow. Therefore, unless the buildings or trees are very close it may not be a problem. Also, for a large part of the year we have diffuse light, not direct sunshine, and the power output is not affected in diffuse light. In winter, the sun is low in the sky, increasing shading but deciduous trees drop their leaves, so most of the light can still get through, and as most of the light is diffuse in winter, no reduction of power.


15) Is Planning permission required?


Normally no – Planning Permission is not required, for either PV or Thermal, even in Conservation Areas, under The Town and Country Planning (General Permitted Development) Order 1995 Schedule 2 Part One Class B. We have a number of replies confirming this, from local authorities, National Parks and the Office of the Deputy Prime Minister. However, if the property is in the curtilage of a Grade1 or 2 listed building, Listed Building Consent is required.


Any temporary structure, such as an array of PV Panels placed in a garden, will not require Planning Permission. Customers should ensure that no special restrictions apply to their properties.


16) Is Building Control Permission Required?


No – The Panels (both PV and Thermal) are not heavy enough to affect the structure of a roof, and of course all plumbing and electrical work has to meet the appropriate new Building Regulations, but as the works are carried by qualified people who can self certificates the works no applications are required.


17) Do we have to Clean the PV panels or Thermal Collectors?


Under normal circumstances, rain will wash off any dirt landing on PV or Thermal Panels. We know of Thermal Collectors, installed for nearly 20 years, that have never been cleaned.

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