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designed for those aiming for modern but sustainable living.
Here you will find articles and links looking at both the environmental and economic benefits of
systems and equipment available to those wanting to embrace sustainable living.
If you are interested in individual sustainable projects, then the links to
these appear below the news items under the various menu categories.
Solar - is a solar panel for hot water worth it?
There are a number of considerations to take into account when trying to answer this question.
The big question affects what your initial intention is - do you want to save money or save the
planet? This article is mainly concerned with the cost side of the argument but we must also look
at the environmental issues if sustainable living is your goal.
Depending on where you live in the UK, the sun will supply around 900 to 1200 kilo watt hours (kwh)
to every square metre of land, and the average person uses around 1,000 kwh of hot water a year.
So, for a family house with a couple of kids we are looking at 4,000kwh of energy for the annual
supply of hot water. According to the Solar Trades Association, a well designed and sized solar
panel water heating installation will supply in the region of 1,500 to 2,000kwh which represents
50-65% of the annual total. Let’s have one more calculation to convert the electricity saved to
CO2 savings. For an average kwh of grid electricity we produce around 0.5kg of CO2 so we are
saving on the above example up to1 tonne of CO2 each year. On the face of it, a solar panel for
hot water heating looks a top idea even in our climate, after all if every house in the UK was
making this saving it would add up to a 22 million tonne CO2 reduction. What this doesn’t allow
for or include is the CO2 generated from manufacturing, transport and installing of all these
solar panels and associated parts. I would be interested to hear from anyone who has data on this
particular aspect so we could update the information.
e above I can only draw the conclusion that there is a real benefit when it comes to carbon
footprint and the drive towards sustainable living but does the maths add up? Carrying on from
the above figures and looking at my last electricity bill, I am currently paying around 9p per
unit (kwh) so I could expect an annual saving of £200 on my bill thanks to the solar if I am
heating it by electric. You have to take into account your own situation, what fuel you are
using, how much your personal consumption is etc.
The installation I have was carried out by myself. I already had the controller and 20 vacuum tube
2.5M2 solar panel which I had purchased from Navitron 3 years ago for a different project. At the
time the collector, Resol controller, pump and their pressurised system kit came to £700. I have
checked the current prices and the similar parts today would cost around £900. Added to these are
the other components I needed for my installation. A 172 litre solar tank from Gledhill, piping,
fittings etc, which all came to another £650 making a total cost of £1,550. If the saving is £200
per year then we have a payback time of getting on for 8 years. The system should last 25 years
but there will be maintenance along the way. My personal feeling is that anything less than a 10
year payback makes financial sense as long as I am planning to stay where I am. Will it add
£1,500 to the value of the property? I doubt it. Will it make the difference to someone’s
decision to buy my house if it were for sale? Again, I doubt it, so I can only see a financial
benefit from fitting this unit if I stay in the property for over 8 years.
This raises a very serious issue. These figures are becoming marginal (if I work on 10 years being
a maximum sensible payback period) at 8 years but if I wanted the unit installed, then the
figures for the solar panel really do go out the window from a financial standpoint. According to
the Solar Trades Association a reasonable installed price for solar power for water heating is
£4,000. This means it will take 20 years to recover your cost, without including any repairs or
servicing costs. At these figures there really is no economic argument to justify installing solar hot water.
Then the idea of renewable heat incentive was invented. This was out for consultation when the
last government was replaced so what will happen to it under the new regime is uncertain. No
decision had been taken at the time of writing this article but the intention of the Renewable
Heat Incentive (RHI) is to incentivise households to install technologies including air and ground
source heat pumps, biomass boilers, solar panel water heaters and combined heat and power (CHP) plants which use renewable fuels. The consultation period closed back in April 2010, but no decisions have been taken by the new government as to whether it will go ahead, be modified or scrapped. If scrapped then it is expected that some alternative will be offered as the government is committed to significantly increase renewables.
So what will it mean to the householder? RHI is a system that would allow those producing
renewable heat to be paid for the benefit they are producing. The plan is for those who invest in
renewables to have their capital costs paid back over a 10 to 15 year period. All those still
using conventional heating sources will be charged a levy which will be used to pay for this
incentive.
On the face of it, this appears to be a positive way to encourage households to reduce their
carbon footprint and help towards sustainable living but it remains to be seen if the savings made
by the householder will make them the prime beneficiary or will the savings be absorbed through
increased costs from the suppliers and installers to cover environmental red tape. The other
concern is that the levy on those using conventional heating will become yet another tax which
will hurt those most who can’t afford the initial costs to upgrade to a greener system. Getting
back to my solar power installation, as I have carried out the work myself it would not be
eligible for any grants or payments and what ever system is brought in, the chances are the only
real beneficiary financially will be the installers.
Living with my installation has impressed me. Even though the weather since installation has been
poor (overcast with the odd glimpse of sunshine), over the past three weeks we have only flicked
the immersion on for 10 minutes, and that was only because we wanted a bath. I am sure if we had a
bit more sunshine, even that would not have been necessary. The days are long in July and August
and I am looking forward to the effectiveness as winter approaches when I shall update this article.
So what is my conclusion? If you truly believe in the idea of sustainable living then forget the
money and the costs, solar hot water does work and you do feel good when you are stood under a nice hot shower and know that the only thing that’s heated the water is the sun!
Want to comment or have something to add regarding solar power?
Then email with your views. Shortly we shall be introducing a comment box directly under each article. Until then, please email and we shall add your comments.