Solar PV 2.1kWp

[CeeBee]

I posted pics of my Navitron solar thermal SFB20 recently. It's now been joined by a solar PV 2.1kWp array. Nothing Navitron about the latter, but well, you can still see the Navitron panel in some of the pictures.

• Men at work in the lovely weather. Navitron thermal panel already in position at the far end of the roof.
• 9 out the 10 210Wp PV panels are visible, and of course the Navitron panel again.
• Stuff in the loft, left to right: AC switch; transmitter for remote power display; inverter; DC isolator switch.
• Stuff at the fuseboard: solar additions are switch and MCB in enclosure at bottom left; total generation meter at bottom right; big red AC isolator switch. You can also see the sensor/transmitter for my OWL (Electrisave) whole house power meter - perhaps should have got the Navitron offering instead, as I think it gives more than just an instantaneous reading. (See further down the thread for an updated photo after export meter was added.)

[frotter]

Drooool... 

[martin]

everybody else has been too polite to ask...............how much?

[ajstoneservices]

C*****,

That is really cool,  looks as if one of the installers is eying up the pub menu. I hope you'll let us know how the system performs.

Hope its not as wet on Wednesday, we're on a roof in Huntington, new boiler/solar.

Tony

[Bill H]

CeeBee,

looks the dogs alright   

Facing south and unshaded ?   Sunny days ahead !

Are you selling surplus back to the grid ?

best

Bill

[CeeBee]

A few replies:

frotter - never mind 'drool' - for my part, I'm envious of the lard-powered Listers etc. I haven't the time, ability, nor tools for serious DIY stuff, so happy to get the professionals in for my installations.

martin - about 12.5k, with hopefully 2.5k grant back off that shortly. So a lot. Most of it no doubt the cost of the panels, not forgetting inverter and other bits. Pity not the 50% grant that some people got up to the start of 2007 (providing they applied in the first few milliseconds of the month).

ajstoneservices - who did my Navitron thermal panel - is no doubt familiar with the pub across the road from my house! In the week so far, the PV system produced about 10kWh on the best day. It's fairly well known what these systems should produce in this country though - about 1900kWh would be expected over the whole year. The inverter claims that peak power so far was around 2150W, so seems in line with it being a 2.1kWp (kilowatt peak) system (I assume kWp is what you'd get under some standard ideal conditions).

Bill H - it points about 30 degrees east of south, and roof slopes at about 30 degrees. There's a chimney at the west end of the roof, which will cast a shadow on some of the panels in the late afternoon in high Summer (it won't have any effect during September-March). The installers reckon the shading might lose up to 5% of potential generation. My present electricity suppliers (Ebico, who kind-of resell power from Southern Electric at good rates, with the simplest imaginable tariffs - check their site) claim to fit an export meter for free, then pay 18p/kWh for power exported (but they take your ROCs - you don't get to claim for ROCs based on total generation as well). This isn't happening yet - still awaiting the appropriate paperwork - so for the moment any export is being provided free. Wonder if there's any chance of some estimated backdating?

I reckon I'm quite economical with electricity around the house, but then I go and blow it by having an electrically-heated greenhouse. Must spend the time to insulate it before next Winter. Perhaps a good application for a heat pump, since it would replace existing electric heating, and would use most during the 'Economy 7' period (midnight to 7am). At least I can guarantee that the 40W pump on the solar thermal system will only use locally-generated power, since it's only needed when the sun's out.

[dhaslam]

A few replies:

I reckon I'm quite economical with electricity around the house, but then I go and blow it by having an electrically-heated greenhouse. Must spend the time to insulate it before next Winter. Perhaps a good application for a heat pump, since it would replace existing electric heating, and would use most during the 'Economy 7' period (midnight to 7am). At least I can guarantee that the 40W pump on the solar thermal system will only use locally-generated power, since it's only needed when the sun's out.

Why not incorpoate heating and cooling with an  underground heat store?  You could still top up with electricity on dull days. 

[CeeBee]

Why not incorporate heating and cooling [of a greenhouse] with an  underground heat store? You could still top up with electricity on dull days.

Risk of thread-drift here - let's start another if we want to continue on this. It's a good idea. One that I'd read about before. Obstacle is just my own inertia - wonder how one would make a huge hole in the ground; stop it filling with water; reluctance to lift the paving slabs forming the greenhouse floor (those were one of my few DIY jobs!). Even on cold Winter days, greenhouses are good at illustrating the greenhouse-effect! They soon warm up if the sun comes out. My auto-vents sometimes open. Would be great to make use of the heat instead. The concrete floor itself is already quite good at absorbing daytime heat, but a lot more could be done.

[Dee J]

Great install

can't wait to get pv as well. Got to get my solar thermal installed first though.

Just a minor area of concern - all that extra install around the meter board at the supply head... some poor meter fitter is going to love that... not. I take it that the Isolator, extra meter, seperate RCBO and those extra tails back to the Henley block are the added install - might have been a good idea to have found a better location for that lot. Looks like it wouldn't be easy to get the lid off the old consumer unit either - sorry - just an electricians whinge.

Dee

[CeeBee]

Just a minor area of concern - all that extra install around the meter board at the supply head... some poor meter fitter is going to love that... not. I take it that the Isolator, extra meter, seperate RCBO and those extra tails back to the Henley block are the added install - might have been a good idea to have found a better location for that lot. Looks like it wouldn't be easy to get the lid off the old consumer unit either - sorry - just an electricians whinge.

Hi Dee

It surprised me that all that clobber went in the little meter cupboard - so far as I'm concerned, it could have gone in the loft, but are there maybe regulations saying that it must be clearly visible to anyone who comes along to fiddle with the meter or consumer unit?

I think you've identified the correct bits - I'm not over-familiar with the names for them myself. I assume the 'Henley block' is the black thing at top right connecting a total of 3 pairs of live/neutral i.e. mains, PV, consumer unit. The installers said they'd have just taken the mains and PV pairs into the consumer unit, but that they wouldn't fit - hence the 'block'.

They did say that while it might look difficult to get the cover off the consumer unit, the 'block' isn't actually fastened to anything, and can be pushed aside enough to get the lid off.

It worries me that some guy from the contractors (most likely Siemens) will turn up to fit an export meter (when they get round to it), and wonder where it's going to fit. If they'd replace present economy 7 import meter by a combined import/export one (I'm sure they exist), then it could occupy the same space, but I wonder if this is too much to hope for. I've tried warning my suppliers (Ebico via Southern Electric), who will be instigating this, and perhaps I'll try again letting the contractors know before they turn up.

[Paulh_Boats]

CeeBee,

The Export meter will probably go on a fused spur between the invertor AC isolator and one side of the Import meter.


Regarding Ebico ...... I'm considering switching from NPower:

First NPower units are 15p, dropping to 11p.   The pay full price + ROC, so only 15p after first units

Ebico units are all 11p. So 18p per generated unit looks better, and no standing charge.

[Dee J]

It surprised me that all that clobber went in the little meter cupboard - so far as I'm concerned, it could have gone in the loft, but are there maybe regulations saying that it must be clearly visible to anyone who comes along to fiddle with the meter or consumer unit?

Charitably...I think they've tried to make the best of a difficult job. Yes that kit does need to be near the origin of the install (i.e. the meter) but just not on the supply company's meter board!(yes they own that bit of chipboard and officially it's reserved for supply company kit) As for not using a connection via the existing consumer unit - the requirements for the pv install specify that the electrical system it connects to has to meet current regs - I don't think your consumer unit achieves that - so they've avoided it altogether by connecting at the big black Henley block instead. To have done a full and clean job they really needed about twice the space your little cupboard provides. Ideally on a £10k job like that, a few hundred replacing your original consumer unit and creating a larger cupboard space would have been money well spent. BTW that black Henley block shouldn't have been left floating - regs/safety issue there. With any luck an export meter can fit in place of your existing meter but maybe plan to get the whole lot revamped in the near future.

Dee

[tony.]

is the meter cupboard out side.
Just a warning, the meter cupboard is generally the property of the lecky board and for their equipmenrt only.

ignoring that, congratulations!!! on the work.

Are the panels mounted on the unistrut by square washers and a zeb or a special hold down bracket?

Just interested thats all

tony

[CeeBee]

is the meter cupboard out side.
Just a warning, the meter cupboard is generally the property of the lecky board and for their equipment only.

No - the cupboard's inside the house. In the photo at the start of the thread, the consumer unit is mounted just above the top of the wooden board with the main fuse and meter (and now all that other clobber) on it. I imagine the consumer unit originally had wire fuses in it, but at some time long before me, they were replaced with MCBs, with the result that the lid won't fit on the consumer unit (the old lid is still in the bottom of the cupboard).

From the discussion in this thread, I can foresee some kind of problem if/when a chap turns up from the leccy network operator to fit an export meter, and finds all the space on their board used up. It surprises me if my PV installers were being 'naughty', as they are reputable, registered, and all that.

Still, I can see me being in the market for a bigger cupboard, and new modern consumer unit while we're at it (any electricians covering Cambridge reading this?).

Are the panels mounted on the unistrut by square washers and a zeb or a special hold down bracket?

Afraid I don't know the termiology ('zeb' etc.). In the pictures, you can see the two clamps between each pair of panels. I recall they are screwed down with something requiring an allen-type key, but would have to get the ladder out to remind myself exactly what it consists of. I assume that the ones on the end panels are slightly different.

[CeeBee]

Export meter finally installed today, so I thought I'd add an updated photo of the fuseboard. After all the discussion above about extraneous components on the "Electricity Board's" piece of wood, I've had them moved off it, and a new "17th Edition" consumer unit at the top (split load, both halves with RCD, enough "ways" for the house, unlike the previous one).

On the main board, we've got import meter on the left, export meter on the right (just in series, obviously one of them the 'other' way round). Solar PV AC from inverter enters the big red AC isolator switch, then the total generation meter, out to the right where there's a switch and MCB in their own enclosure, then to the black "Henley Block" where it meets the mains supply and heads off to the consumer unit. You can see the sensor/transmitter for my OWL (Electrisave) whole house power meter - presently on one of the cables showing the house consumption regardless of whether it's coming from PV or the main supply.

All I need now is a nice new cupboard round it all - old one demolished to make room for all this stuff.