1 year of solar panels + energy costs…

It’s been 1 year since we had the solar PV panels installed on the front roof of our house. It’s been a really inspiring and life-changing experience in many ways and we’re more aware now of how much energy we’re using and what times of day it’s best to use certain energy-intensive appliances.

So, over the year, the panels produced nearly 1250 units of electricity, which will give us around £540 from the feed in tariff (at 43.3p per unit) and equaled 43% of the electricity we used.

The types of fuel we’ve been using are wood, gas and electricity. For gas, there is an equation which the gas companies use to convert the metric units of gas which is burned in the boiler or oven/hob to a KW/h ‘unit’.

units used x calorific value x volume correction / conversion to KWh = gas used in KWh

This is… X units x 39.3 x 1.022640 / 3.6 = X KWh

This allows you to compare the actual energy that is used for gas and electric, in a comparable unit, in this case KWh. This is a bit geeky but the figures below (even for what turns out to be our very low usage) are pretty big, especially when the gas and electric consumption is compared with what our solar panels are generating. Here are our figures for the last year…

(01/01/2011 to 01/01/2012)

Gas = £249.18 or 3371 KWh

Electric = £374.52 or 2923 KWh

(01/02/2011 to 01/02/2012 – our 1st full month generating was February 2011)

Solar panels = £540 (income) or 1248.9 KWh

So, £623.70 spent on gas and electric for the whole year. Add to this the £360 for the 6M3 of firewood for the space heating of the living areas gives £983.70, which is the total spent on fuel/energy for the year.

The total in energy terms (KWh) was 6294 for gas and electric. I’m not sure how to work out the KWh provided by the wood though??

From the cost of £983.70, the income from the solar panels should be deducted (£540), giving a grand total spent on energy for the year of £443.70!

Two really important issues come out of this. The first is the comparison of KWh totals for generated and used, as follows.

Total generated = 1,248.9 KWh

Total consumed = 6,294 KWh

There’s obviously a bid difference there and even with the solar panels, with the consumption roughly 5 times more than the generated (or even more if you add in the unknown energy value for the wood). Solar panel efficiency has got a long way to go before it’s able to claw back some of this difference.

The second thing to highlight is the ‘average’ figures for 3-bed semis, which all the price comparison websites use for their standard figures. These are their figures for consumption per year.

  • Average electricity usage of 3,300 kWh for standard single rate electricity that’s averaged across all regions and
  • Average gas usage of 20,500 kWh per household

Assuming 8p per KWh unit of gas and 10p per KWh unit of electricity would give…

Gas: £0.08 x 20,500 KWh = £1,640

Electric: £0.10 x 3,300 KWh = £330

Combined total = £1,970

If this total figure is used as a comparison, our total of £443.70 is amazing. This is 22% of the average and i’m proud that all the combined features we’ve installed and the way we live has led to this figure. It makes all the chopping of the fire wood much more appealing!


Solar: Feed-in Tariffs…

Slightly old news now, but here it is none the less… the expected but still harsh cut to the single biggest motivator of renewable solar technology in the UK – Feed In Tariffs.

In my humble opinion, the solar renewable energy industry has not had time to grow and sustain itself – the level of FITs need to be in place for a number of years first (as in the 11 years in Germany). Halving the rate is going to take the free panels schemes out of the residential market, as there will be very little incentive for private companies to provide them.

‘On Thursday, Germany, the world’s biggest solar panel market, said it will also cut subsidies for solar photovoltaic power. Rates will be reduced 15% from January 2012, the Bundesnetzagentur, the federal grid regulator, announced. Power from panels will earn between €0.18 and €0.24 per kWh, depending on size and location.’

‘Deep cuts to the popular tariff have been overseen in recent years, with the German government arguing that economies of scale and improvements in technology are resulting in rapid reductions in the cost of the sector, meaning the industry no longer needs such a high-level of state aid. Since Germany’s Renewable Energy Sources Act (EEG) was introduced 11 years ago, providers are guaranteed fixed prices for the electricity they feed into the grid. Like the UK scheme it is paid for by consumers, adding €0.036 per kWh on energy bills or, according to calculations by the Rheinish-Westphalian Institute for Economic Research (RWI), €85.4bn for the solar built between 2000 and 2010 and ensuing payments.’

‘The Bundesnetzagentur revises the tariff regularly. A 9% reduction every year is given by law, but it can be higher depending on actual new installations.’

Johns told the Guardian that the cuts would be a “disaster”. “If they go ahead with this, the tariff is way too low, and all the social housing and free solar schemes – which make the feed-in tariffs exciting in terms of fuel poverty – will be destroyed.” He added that this was the third government review into solar subsidies this year, saying: “We’ve invested business in PV [solar photovoltaic panels] and had it sliced up three times in a year. They [the government] have no credibility on this any more.”

Germany, as ever, provides the case study to follow here. They have built up a strong dominance in the solar market (certainly in Europe) by providing a stable and incentivised solar market. They didn’t slash their FIT rate after 1 year, rather they steadily reduced it over a period of 11 years, with the full knowledge of all involved.

The cut to the UK tariff is so severe that it will take out a large proportion of the whole market in one blow. Yes the 43.3 pence per KWh tariff is unsustainable, but this is needed to get technologies off the ground and to establish markets. Just as this was starting to happen, it all changes dramatically. Very annoying and a shameful lack of support for our renewables industry.


Blackfriars Station solar panels…!

Britain’s largest solar array – when it opens next year! More than 4,400 panels in total.



Solar panels hit 1 Mega Watt…!

It’s official, even following some months of fairly dull weather (it looks like the real summer was in March and April), our electricity generation from the solar panels has hit 1,000 KWh!

This is the same as one Mega Watt (1MW) and is enough energy to continuously boil a 3,000W kettle for more than 333 hours*!

* 1 unit of energy (1KWh) = 20 mins of boiling time for a 3,000W kettle, multiplied by 1,000 units, divided by 60 to convert into hours.

It’s an incredible milestone but it’s also worth considering that the total produced by our 1.72KW system will produce enough to cover maybe 3/5 of our total electricty use. We still use more than we can generate and the peak times are the opposite of when the sun is shining – the major inherent problem with solar as a reliable energy source!

Even considering this, it is still a major dent in our consumption and we have been effectively providing clean, renewable energy back into the grid for a whole year, which all of our neighbours have been using.

The other major positive is the Feed In Tariff of 43.3 pence per unit will mean we recieve £520 (if the total for the year hits 1200 units, which is realistic). Plus 3 pence per unit for the Export Tariff will also add into the total.


Electric meter spinning backwards…!

Another record solar panel electric day – 5.9 units (5.9 KWh)! Previous record was 4.6 units.

I glanced at the electric meter reader when I got downstairs today and it said 850W on the screen. The only thing using power at that point was the fridge freezer, so there was something odd about that, given that the fridge only uses 12W of power!

I knew that the remote electric reader measures the flow of electricity, not necessarily the usage – in most houses the flow only goes into the house, not out!

So I looked at the electric meter and it was spinning backwards – Yes! I’ve waited years to finally see that happening and it was an amazing feeling. It’s obviously been spinning backwards at various points so far but i’ve just never seen it. So, at the peak output for this time of year, it’s producing roughly 850W of power, which we’re being paid to produce but which is also ‘free’ to use in the house.

* I forgot to add that we have also passed the 100 unit mark (now 107.5)!


FIT record broken…!

Ok, yesterday was the best day so far for electricity produced by the solar panels. There was a total of 4.8 units, which is 4.8 KWh, which is 4800 Wh. Each KWh is basically 1000W per hour, or put another way, it is enough to power a 1KW appliance for 1 hour.

So, if your kettle uses 3KW of electric (which is standard), yesterday the panels would have produced enough electric to keep the kettle boiling continuously for more than 1.5 hours! Awesome technology.

I’m just getting very excited because we had the panels installed at the end of December, so have only seen the output during the two worst months for sunlight! March is the start of the upturn, where the output doubles, compared to the previous 2 months!

Today is also looking like a clear and bright day, so maybe another record. The other new technology we have just had ‘installed’ is the insulated exterior render, to the side and rear of the house. Before the render was applied, the internal temperature was roughly 10 degrees C. more than outside. For the last few days, the difference has been 15 degrees C! The last couple of days, the outside temperature at 8 in the morning has been Zero degrees C. and inside it’s been roughly 15 degrees C. It’s a big improvement but we’ll still need the fire on in cold weather, but not as much and for shorter periods.

So, the Feed-In-Tariff (FIT) will be giving us 41.1p per KWh, which will rise to 43.3p per KWh as of 1st April. This means we get 41.3 pence for every unit we produce.

‘In 2008, a detailed analysis by the European Commission concluded that “well-adapted feed-in tariff regimes are generally the most efficient and effective support schemes for promoting renewable electricity”.[9] This conclusion has been supported by a number of recent analyses, including by the International Energy Agency,[10][11] the European Federation for Renewable Energy,[12] as well as by Deutsche Bank.[13]

‘Some have argued that feed-in tariffs can be used to accelerate the pace at which renewable energy technologies become cost-competitive with electricity provided from the grid. The rapid deployment of renewable energy under feed-in tariffs seen in countries like Germany, Denmark and Spain has undoubtedly contributed to reducing technology costs, and hence, in accelerating this trend. For instance, wind and solar technology costs have decreased dramatically since the 1960s and 1970s , as the technologies have become more widespread, manufacturing processes have improved, innovations have been incorporated, and gains have been harnessed from economies of scale.’ (Wikipedia)

Government have brought forward their review of the FIT scheme to 2011! Not a big surprise considering how many large companies were setting up massive 50KW arrays and getting the FIT rates! But, this may hit the residential market if the FIT rate goes down too much. It was always likely to come down but the window of opportunity is closing with a very restricted time frame.


House progress…?

Ok, so there’s been very little tangible progress on the house since the solar panels went in and things have been quite delayed. The panels should have been installed after the insulated render, given the render is more of a priority! But, with the coldest December on record and one of the coldest winters for a generation, the work on the render has been put back. This is mainly due to the fact that for the render to set, the temperature has to be minimum 3 degrees Celcius, over a 3 day period. Obviously this hasn’t been possible for a while, so there is now a back-log of work which the contractor has to get done.

It’s a bit of a shame given how cold it’s been – we could have really done with modern-level insulation for our leaky Victorian house! Anyway, the panels are on the roof and are generating a small amount of leccy and work on the render will start within the next 2 weeks.

The really key thing i’m looking forward to is the work to brick up the very leaky loft window and the new loft hatch. Cold air gets right through into the house now and we’re constantly fighting against the cold coming in. The hallway area is also being plastered, meaning we can basically finish up there and get some fitted carpets in, also for the stairs.

I’ve also fitted some new shelves to the side of our main fireplace, which has made a big difference to how crowded the main bookshelf looks. Just have to paint those. We’ve also had a sort out of toys and furniture in the living room. We’ve culled lots of old toys and brought down a wooden ottoman chest from the loft, to store our mass of wooden train track. Next job is to tackle the under-stairs cupboard and to fit a series of floor-to-ceiling shelves.

So, things are moving on but we’ve been seriously slowed down by illness, the cold weather and Christmas! New year and new motivation – it’s going to be a good year!


Snow-covered power station…!

Well, the roof-top power station is hardly running at full capacity right now!

So far, since Friday 17th December at 1:30 pm, the whole array has generated 0.7 units of power. This is a massive £0.29 at the feed-in tariff rate of 41.3p / kwh (unit)!

Paul from Target 2050 has just come round to complete the installation check, before they can the funds for the grant money. He seemed happy with it, even though the panels are under 10 cms of snow! He did say that the panels generally make most of their electricity during the 6 months over summer, but it will tick over during the clear winter days (providing the panels are clear).

As you can see above, Paul also sent me a link to his own website which has various figures for his own PV system, over the years. Very interesting numbers in there and there’s also a fair bit of variation between the years for the same months.

Anyway, you can see the general pattern, so we’re looking forward to the Spring months where output should go up a bit.


Working weekend…

So, we had a really productive weekend and I feel like we got a lot done. On Saturday I shifted everything from the upstairs landing while Claire was at one of our friends kids birthday parties. It was 2 hours of non-stop fairly fast work needed to get everything shifted about. I had to get the two wardrobes moved into each of the bedrooms and also move everything about in the back bedroom.

The whole point of all this activity was to clear the landing area, ready for plastering work in the next couple of weeks. This is part of the work to render the house, which also includes a new loft hatch and blocking up of the loft window. So, all of that work needs a clear space, which we essentially now have (minus a few bags etc which can just be shoved in one of the bedrooms!).

The following day we all went out to the front garden to generally tidy things up a bit for the winter, but mainly to swap the flower beds which surround the front bay window, to the beds which are next to the pavement wall.

Part of the reason for this was to clear the base of the front wall of the house, to stop any moisture seeping through to the brickwork. This will also give us a chance to scrape off the old masonry paint and re-apply. The soil had been pressed against the wall and could eventually lead to problems. We’re going to put some kind of shingle/stones in there, with lots of plant pots on top.

We’ve had an amazing year of growth in that flower bed, including a Bay, Lavender and lots of Sunflowers + we had a few Borlotti bean plants in there which were quite productive. We also collected a load of lavender heads and also bay leaves and Rosemary.

The other reason for getting this sorted is the imminent arrival of the scaffolding for the solar panels. This will be setup on the 10th and we wanted to get everything cleared away from the base area. We moved the lavender plants to the opposite beds and hopefully they’ll be ok, particularly, given the freezing weather and snow!

Jamie was out there helping me shovel soil into the big wheelbarrow for 2 hours! He was also playing with his monster truck in the soil and using his little wheelbarrow to shift the soil. He’s really happy outside helping out.

We also all sat down and made some bay leaf-based things and I also finished off the Christmas door wreath, with some bay leaves, rosemary and a head of lavender.


PV solar panels…

We’ve just heard that the new solar panels are being installed before Christmas, on the 13th December! We’ve sent off the contracts to the grant people and have fully mentally committed to the idea. The panels were always part of the whole plan for the house, and a major reason for ripping out the central heating system (why??) before installing our electric radiators!

The idea is to run the electric radiators in both the bedrooms directly off the panels. There is also one in the living room, but we haven’t needed to turn that on so far, as we have the wood burner. This system of using the solar panels, including the wood burner, will be much more sustainable than either gas central heating, or the combination of electric radiators and wood-burner.

So, Green Solar Solutions Ltd have given us 2 quotes for 2 different sizes of arrays. The first was a slightly larger system, at 2.1 KWh and a smaller one at 1.72 KWh. To give an idea what this means, the 1.72 KWh system (which we’ve gone for), is made up of 8 panels, each producing 215W when running at ‘peak’ output – i.e. late morning on a clear day (winter or summer). These outputs add up to the 1,720W (or 1.72 KW), which is enough to power the computer, TV, washing machine, fridge freezer and all the lights, at the same time.

The idea I also had was to switch on the radiators in the bedrooms during the day then just close the doors, in order to benefit from the ‘free’ energy’. We ‘Feed-In’ all of the electricity we produce to the grid, but we also get to use all of the energy we produce as well! The 1.72 KW system will generate a minimum of £500 a year income, from both selling the energy and also saving about 50% on our electricity bill.

Given the quote for the larger system was too much, we had to settle for the smaller one, but this is more within our means and therefore more sustainable. If our idea is to be more sustainable (in all ways), getting into loads more debt doesn’t make sense.

So, the quote was £8,691.90 (including 5% VAT). We are only able to afford to do this because of being on a sustainability ‘Target 2050’ grant scheme, which we originally applied for but didn’t get, but now we’re on it as a couple of people pulled out. The wonderful people at Severn Wye Energy are giving us a 50% grant for the work, which = £4,646.80 fully installed.

This works out as £2.7K per KWh, with the grant. Without the grant, it’s more like £5K per KWh, which is still a standard price right now.

In terms of an investment, it’s a 11% annual return, which is 100% ethical, reduces our carbon footprint and produces 100% renewable energy which is fed back into the grid. Even without the 50% grant, the return would be roughly 6%, which is a lot better than most investments.

So, we’re really excited about the whole thing and can’t wait for the work to start!


Glastonbury solar panels…

Yes mate! I’m was smiling a lot while reading the Guardian article about Michael Eavis and his new solar array – the biggest private array in the UK!


£60,000 per year income, paid back in 9 years. 200 Kilowatts of power. 100 tonnes of Carbon saved per year. Brilliant.


Windows, render, solar panels…

Surveyor from the 2050 grant scheme in the morning.

This guy looked like some aged hippy from back in the day! He’s had solar panels for 6 years and had a slightly manic look about him. One interesting fact from him… did you know that in 1970, the average internal temperature in the home was 15 degrees C, whereas now it’s 22 Degrees C?

Anyway… we are officially on the 2050 grant scheme! Someone apparently dropped out as they spent 3 months faffing about with quotes etc, then in the end said the internal insulation would cause too much disruption. The grant people were offering to pay for 75% of the work cost! It’s like saying here’s £4K, do you want it? No thanks, it’s too much hassle. Fair enough.

See my previous post about the 2050 grant.

Well, the guy says we’re on the scheme and this entitles us to a 75% grant for the external insulated render and also a 50% grant for solar PV panels! Brilliant. If we hadn’t signed up to the scheme, the funds would have gone to a Passiv House in Exeter! Everyone we’ve talked to wants to keep the funding for Gloucester, in Gloucester.

This means that the render will now cost £1,500, down from £7,500 (with another smaller grant also taken off) and the PV panels are now something like £4,500, down from £9,000. We got a quote and survey for the panels a year ago, with the cost coming out at roughly £6K per KW generated. The system we had designed was for 2 KW, meaning roughly £12K. Since then, prices have come down, due to demand, meaning that now it is only £4.5K per KW.

An average 3-bed semi would use something like 2.2 KW annually, so the 2 KW system is about right. The feed-in tariff of 41 pence per unit right now is amazing value and because of this, we will be able to sell each unit back to the grid for more than 4 times what we buy each unit for (roughly 9 pence). This means that the PV panels will be making us £700 per year + we will be getting all the electricity the panels generate for free.

So, in exchange for these huge grants, the Council wants to use us, but mainly the house, as an eco case study for renovations of a Victorian semi-detached. No problem. Most people live in older properties and the work we’re doing here will hopefully inspire other people in older properties to consider similar improvements.

So, James from Safestyle UK (windows) has also just left, after getting here at 6pm. We’ve just signed up for two new windows at the back of the house, one in the bathroom and one in the bedroom. They are technically “B Grade’ which is roughly 1.6 U-Value for the whole window and 1.36 at the centre. The lower the U-Value the better as this is a measurement of how much heat passes through the material, in this case two pains of glass and an Argon-filled air space. Current building regs specify 1.8 for a double glazed unit.

The idea is that the windows are installed on 8th November, then straight after, the render is installed. We’re still very hopeful we can afford the solar panels, and if we can, these can be installed at any point up to the end of the year (or at least signed up to or ordered). Given all this, the house will be insulated and powered. The income from the panels will be used to offset the cost of the loan we’re having to get to pay for most of this! We will also not be using as much electricity for heating, especially as we’re also selling our tumble dryer.


Ethical solar panels…

Here’s some info on what the Ethical Consumer Magazine reckons are the best choices right now in the market – i.e. produced by companies who aren’t in the arms dealing or oil business (BP) + who don’t dump toxic wastes everywhere.

‘The best buys are GB-SolSolarcenturySolarWorld and Yingli Solar.’