Thursday, 26 January 2012

Woodbrooke has solar PV!

Almost two years ago (March 2010) I posted here about Woodbrooke's then new solar hot water. It's been working away ever since then, directly supplying our kitchen and laundry, which have heavy daytime use of hot water. This saves Woodbrooke money on our gas bill as well as reducing our carbon footprint.

Now we have solar electricity as well.

It was all brought forward and completed against the clock because of the government's sudden announcement about the changes to the feed-in tariff (this is the amount that you get paid for the electricity you generate from solar panels - it was originally set at a sufficiently high level to encourage people to install them).

The rate was always planned to be reduced from April 2012, reflecting the reduced price of panels, but the government tried to bring the lower rate in by mid-December, with little notice, and before the so-called consultation period had even ended. This caused great difficulty for householders, charities, local authorities and businesses who were part-way through getting an installation approved, and even greater problems for the whole renewables industry. Their willingness to invest in new technologies and staff training requires a stable, predictable business environment, which the government had, at a stroke, undermined. It has already cost millions of pounds, and tens of thousands of jobs are at stake.

Solarcentury, Friends of the Earth and HomeSun (representing three different kinds of interests in the matter) challenged the government in court and on 15 December the High Court ruled that the sudden change was unlawful. The feed-in tariff (FiT) rates were held at their previous level while the government appealed the decision. This week, on 25 January, the Appeal Court upheld the decision of the High Court. The Department of Energy and Climate Change (DECC) has announced that it is seeking leave to appeal again, this time to the Supreme Court. However, the likely delay in such an appeal even getting to a hearing means that the FiTs may now revert to the original plan, decreasing from 1 April onwards, although this is not yet clear. This whole process has been an unintelligent and appalling waste, by the government, of time and public money .

So, here at Woodbrooke, we now know that our haste wasn't needed - but no matter: during all those bright, cold sunny days that we had in the middle of the winter, our panels were producing green electricty sooner than they would otherwise have done. Even with the sun low in the winter sky, our monitoring meter showed the kilowatt-hours clocking up.

Enough of the politics, here's more about our installation.

The side of Woodbrooke that looks towards the lake faces a little west of south.

When we had the solar hot water installed, the brackets to hold the tubes were placed off-square to the roof in order to face due south for maximum solar gain.

When it came to installing the solar PV panels, we had thought that the same thing would be done - brackets would be mounted on the flat roof and angled so that the panels faced due south.

However, this made less efficient use of the space - angling the panels due south reduced the number of them that could be fitted onto the available roof space. By keeping them square with the roof, more panels could be fitted, and this was beneficial overall - the slightly reduced generating capacity caused by the angle being west of south was more than outweighed by the capacity of the additional panels.

The whole array can be seen here. The system has an overall capacity of just over 10kW and will generate something over 8000kWh in a year.

There are two ways that we can monitor what is going on. A small unit, sited on a table in our entrance hall, gives a real-time readout.

And more detailed information can be displayed on the PC screen of the member of our management team who is reponsible for this aspect of Woodbrooke's work.

 And the panels are well hidden from view (important, as we're a listed building). From the ground, you can see hardly anything at all - to take this photo, I was standing on a bench!

For information on smaller domestic scale solar PV installation and operation, see

1 comment:

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