A site for some of my micro generation projects!

I should add, this site is not complete, and will be added to on an ad hock basis as and when I have time

Solar PV Installation 3.33kW

From 18th March 2007 - 19th March 2008 we have generated 2837.48kW of green power
(Approx 7.77kW per day)

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  • I've recently gone through the exercise of getting quotes to have a full PV system installed and feel someone else may gain something from my experience.

    I started the exercise off about 15 months before the actual install. I contacted a number of 'accredited' installers and even took the time to visit one.

    My wife and I choose to visit one company, so we made a prior appointment to meet up with the main guy. When we arrived, we discovered the 'main guy' had gone out and hadn't let anyone else know of our appointment! Anyway another guy decided to show us around the various systems they had installed (wind, PV, solar water) at their site. He really didn't seem interested in selling us anything, and continually chewed on a matchstick. His parting comment said it all. He said something to the effect of that PV panels wouldn't pay for them selves, you only install them as its a nice thing to do! From this visit we never received any follow up calls.

    After leaving the above company we felt really deflated about the whole issue. I searched around for other local companies. We again made an appointment with another company who came to visit us providing we paid a 150 (refundable if we go ahead) for the visit and to receive a quote! Anyway on the appointed day the company representative came to visit us (we're now quite a few months down the road from the visit to the other company). Well, it only turned out to be the guy who showed us round the first place! So being the blunt guy that I can be when pissed off, I reminded this representative of his attitude when we first met. This obviously did some good as he was far more pro-active this time. From this visit, we did establish the roof we wanted to use was at the wrong angle, as it was too flat. Since we were going to re-cover the roof that wasn't a problem as we took the opportunity to have the gable ends built-up to increase the roof angle. We didn't go for the full 35 degrees, as the roof apex was getting a bit too high. Basically we wanted to keep it under 4 metres, just in case we had to apply for planning permission (we may be wrong, so don't copy us without checking first). Strangely the rep didn't ask for the pre-agreed 150, perhaps that may have been something to do with me biting him!

    I also contact several other companies on an increasing radius from us. The second furthest away, couldn't be bothered to get back to me, even though I made contact several times. The third company (about 45 miles away) came a week later than agreed (he turned up in the top of the range BMW - hardly gives the impression of being green! or at least shows there is money in this technology. Back to the BMW, I do appreciate it may be greener than my ancient van with a 2.5L diesel). I also received a price from a fourth company who were quite a distance away from us. Since the quotes I received were all quoting for different outputs, I contacted them all again to quote on a like for like basis, or at least to achieve the same output using the same Sharpe 185W panels. The first company and the third (remember the second didn't get back to me, so will continue to cal them the third company) had prices which were almost the same. And the other was about 5% more expensive, I put this down to the travelling. Whilst chewing over the prices, I noticed there was a charge for delivery of the panels which I objected to, especially as all the suppliers I deal with, give free delivery for orders over a 100 (inc solar panels)! That was wiped off. Now these companies started to ring me on a regular basis, so as it was part of the deal that the first company would apply for the grant on my behalf, I got them to do that (this was November 2006). Less than half an hour later I had an email from the Energy Saving Trust saying I'd had my grant application approved. Seems like I was very lucky on this, as apparently you have a job to get grants now. Anyway Christmas came and went, builder dragged their feet, as is normal (still waiting for the gutters to be replaced). More calls from the installers to see if I'd made a decision on who to run with, so eventually got round one evening to go over the paperwork. The third company sent me 8 pages of literally small print of terms and conditions, talk about going over the top! Only had to sneeze on the panel and they would do a runner. Partly on that basis I decided to run with the first company. Unfortunately for me, the first company then rang, so I told them they had got the job. Before I could finish writing a letter to the third company to say they had lost the job, they rang up. Obviously they were very disappointed. Several minutes later, their Director was on the phone offering a 10% discount. Doh.... Yes I could have gone back on my word and saved my self a couple of thousand, but I'm a man of my word, and wouldn't like anyone pulling out on me (yes I've had it done to me), so continued to run with the first company.

    During discussions with the third company and their over the top T&C's, they explained they are obligated to send them out by the Energy Savings Trust, as its also part of being an accredited installer, so was annoyed that no one else was doing the same.

    Perhaps if your in a similar situation, its possibly worth while saying your going to run with another company, to see if your going to get offered some discount. I think part of the reason for the third company trying so hard to get the job, was they weren't fully accredited, and wanted some jobs to have a bit of a portfolio for other potential clients, plus obviously to get full accreditation.

    Anyway, paid up the 10% deposit to action the installation with the first company. I've dealt with many contractors and builders over the years, so was taken aback by this companies customer care, as they rang the week before to check everything was okay to start the following week, then on the appointed day, they rang again to say they would be with us in an hour. When they arrived, they all introduced themselves and shook hands. If they left site, they again said they were leaving and where they were going. Obviously these guys have a different attitude to the environment, as previous contractors I've had on site would leave their empty coke cans, snack and crisp packets everywhere, these guy's brought fruit juice, fresh fruit and took it all away with them! The installation took less than two days to mount 18 panels on to our new shed roof. The grid-tie inverter was installed next to an existing consumer unit in the shed. Following completion, we paid up the remaining 90%, so we're currently waiting for the Energy Saving Trust to pay us the grant money. Apparently it used to be a case of only paying the installer the full price, less the grant allowance, then the grant would be paid directly to the installer. Sadly its now a case of paying up the full amount, then wait for the grant to pay us back.

    One of our present occupations is watching the electricity consumption meter going backwards Very Happy Whilst the panels output doesn't always cover our consumption of power, it has made us very aware of what power we do use, which is a benefit in its self. We're going to benefit more than most, as we work from home, so consuming the power as its generated, rather than selling it to the supply company at a low rate, then buying it back at a higher rate.

    Our follow-up project is a web cam in the meter cupboard.... just joking Wink , its a home brew wind generator which will be shown on other pages of this site. The wind generator will initially will give us hot water via an immersion heater. Later after collection of suitable bits at the right price (minimal budget project) we will use the wind generated power to power the home via an existing 2KW UPS unit that currently powers our PC's.

    If you have any questions etc. do get in touch.

    Click on any pickie for a larger view in a fresh page

    Our PV array consists of 18 Sharpe 185 watt panels wired in two strings, so each string gives 216 volts (Note to me - need to check this data!)

    This is the original shed roof, which consisted of rusty corrugated steel sheets. The intention has always been to replace the roof covering, so carrying it out prior to the PV installation was an ideal time. Following several visits from PV installation companies we also decided to raise the pitch of the roof, as it was far too shallow. We didn't take the pitch up to the recommended angle, because the apex would have been too high (we were about 6" lower). By being too high, I mean this may have had planning permission implications, so we decided to keep it just under the height that is allowed before planning permission is required.

    The new roofing sheets are plastic coated box profile sat on top of a polyurethane type insulation material. The rough size being 10 metres (approx 33 feet) by 3 metres (approx 10 feet) from gutter to apex. As pointed out above, we increased the pitch, which raised the apex by about a metre (3 feet 3 inches)
    The roofing materials have been mounted on roofing grade purlin's and trusses. The insulation material is foils faced, hence the sheen shown below. The building is used to store wood for our wood burner (which also heats the whole house), so masses of insulation is not required, however it does stop the condensation dripping everywhere.
    Inside the shed is the control panel for the PV array. To the left is a standard consumer unit (fuse board) which is fed from the mains supply in the house, then it also goes on to another building. The PV system is simply connected to a spare fuse in the consumer unit. Moving right slightly, above the white plastic trunking is a total generation meter, right again is an isolator which is fed from the consumer unit and is then connected to the inverter. Right again is the PV array isolator which isolates the PV panel supply from the inverter. Finally on the far right is the 'grid-tie' inverter. In preparation for future projects, I mounted quite a large board (over the top of more insulation material - not completed), thinking there would be plenty of room for all the PV stuff, and some bits of mine. However the PV installers decided to use it all for them selves Doh....
    This is the total power generated meter with high tech label! There's a little led that flashes once for every 100 watts generated. Its a pleasing sight to watch this - simple pleasures Apparently this meter is accepted by power suppliers for your generated power outputs, so when registered with a particular company, they are happy to accept your readings from this meter to make cash credits to you.
    The 'grid-tie' inverter is made by Fronius and is G83 compliant, which means its an approved piece of equipment that power supply companies are happy to you use to supply power back in to the nation grid. The illuminated display doesn't show up all the time, but for display purposes I've pushed the button to clearly display the amount of power being generated. I had thought about adding an exterior photo cell to isolate the supply during hours of darkness to conserve power, however in darkness the unit shuts down and only consumes a fraction of a watt per hour. So my addition would have been a waste of time. Whilst we have got the 'basic' unit, I see in the manual extra cards (like in a PC) can be added, such as an interface to a PC to monitor power outputs etc. I don't know what these cost, probably not cheap. The inverter actually hums when generating, and its volume is greater as the power output rises, so its nice when getting things out of the shed to hear it humming loudly

    Another feature of the grid-tie inverter is that it will only export power when it detects national grid power. This means if you have a power cut, it shuts the system down. This is for safety, as its important that it shuts down in a power outage situation, as the power supply company may have shut the power off to work on their system, so to have our PV pushing power back in to the grid would be very dangerous for anyone working on the grid system when they thought they had isolated the power source!

    Nothing extraordinary here. This is the main consumer unit and power supply companies meter in the house. The meter is the dial type which actually turns backwards when we're exporting power. I'll try and add a video clip sometime.

    As the consumer unit is a dated Wylex unit with rewirable fuses, the future intention is to replace it with a couple of new units with trip switches. The idea behind splitting the current circuits in to several board is for future energy generation projects, so heavy loads like the electric cooker would be on a board fed directly from the grid, where as lighting circuits would be fed off another board which would be fed by an off-grid system which I intend building at a later date.

    All the stickers on the consumer unit are to comply with British wiring regulations and safety. Our house wiring colours are red for live and black for neutral, where as in January 2007 the BS wiring regulations changed to move in to line with the wiring colour scheme used in the rest of Europe, this being brown for live and blue for neutral. So the one sticker warns that two colour schemes are used. Since January 2007 the government also changed some of the building regulations, and a scheme generally referred to as 'Part P' wiring regulations came in to play where only certain qualified tradesman can carry out electrical work. Since the colour scheme also changed at the same time (at this time, it was no longer possible to purchase cables such as twin and earth in the old colour schemes) as the 'Part P' came in to force, it then became easy to identify what wiring changes were made after January 2007. All electrical work (there are exceptions) must be supported by an electrical test certificate, this being supplied by the electrical contractor, or for a fee, the local building officer can supply one. Back to my local issue.... the second sticker informs that two electrical supplies (PV power and national grid power) are fed in to the consumer unit, so to take action to isolate both supplies when working on the system.

    This is a schematic diagram of our system, which we need to post by the inverter and another by the consumer unit in the house. Its basically self explanitory.
    This sheet was supplied by the grid-tie inverter manufactoerer.

    I do have some more bits of info to add, so keep calling back.