[Colonel Panic]

Is there any benefit it making an array sun following ?

There must definitely be a benefit, but not sure it would be financially viable in Scotland (or in the SE for that matter!).

I'm impressed with your turbine output !

NB: AIUI, with new installations one gets no payment for any energy exported to the grid at all

[Flyin'Dutch']

NB: AIUI, with new installations one gets no payment for any energy exported to the grid at all

No doubt the joint up government thinking at work!

Quite what thinking that is, is anybody's guess but hey ho!

[malcolmfrost]

Where you live I guess wind is more reliable than solar! Down here my panels have generated 22kWh today alone, Ok it's been very sunny but I reckon that's really good, enough for around 60 miles in a Tesla and free!

How many panels do you have? I've generated 25.8kWh, and exported 11.4kWh. And even at 20:07L we are still generating 32W

(Our system is nominally 4kW / 16 panel, but with ~3% transmission loss between the panels in a field and the house).

I've got the same but I lose half the panels at around 6 as the sun goes behind a perpendicular roofline.

[kanga]

NB: AIUI, with new installations one gets no payment for any energy exported to the grid at all

No doubt the joint up government thinking at work!

Quite what thinking that is, is anybody's guess but hey ho!

Perfectly joined up thinking. What changed was a change of Government with different philosophy and priorities

[Colonel Panic]

I can understand how any government might choose to end small scale energy generation production subsidies, but it does seem fundamentally bizarre to end being paid for energy transferred in to the grid.

[NB: The intention was to scrap this part of of the FIT for newcomers from 01-APR-19, but it is not clear on 't web that it has actually gone. I hope I haven't misled anyone here]

[Flyin'Dutch']

Putting my tin hat on I can only think they don't like small scale generation as it takes away the monopoly of the big energy generators.

There are now in roof solar panels where you cannot see that they are panels at all. It would make sense to have those mounted into any new roof. That would be 30% of electrical needs for those households sorted in one go.

[kanga]

It was the formal policy of the Coalition Government that all new build houses should be required to have solar panels (and much better insulation), with long-term intention that all residential property should eventually be net zero energy user. This policy was dropped very early after the 2015 election. I would not presume to speculate on the motives and lobbying behind this change ..

[Flyin'Dutch']

You are too polite!



They also dropped any support for on shore wind farms. Can now not remember whether that is just no subsidies or also no further development.

In Germany, which still does support wind and solar development, there are quite a few days that the power supply for electric is 100% provided by renewables. Unfortunately on days that this is not the case they reckon it is a brilliant idea to burn brown coal which is clearly plain stupid.

[OCB]

Bill, I did the maths a few months back - the expense and hassle of the electro-mechanics behind sun following for a few panels isn’t worth it - unless you plan moving to Southern Turkey or whatever.

It’s one thing I’d be curious to know - is whether ground sourced heat pump would be worth it where you are.

I think we discussed this before, but at minimum - having an uplift on the incoming mains water before it hits a boiler is both a near no-brainer in terms of plumbing, and in terms of reducing what oil/gas/leccy have to put in to get DHW up to the temperatures required for bath/shower etc.

[Trent772]

Sun following costs nothing and involves no motors or electrics.

My buddy in California had an array of 6 big panels on poles oriented true south.

The panel had a black tube and a white tube on the east/west side and a bungey to orient it east facing in the morning.

The tube had a volatile liquid in it, so in the morning, the volatile evaporated in the black side and transferred to the white side. This altered the balance of the panel and ever so slowly it tracked the sun. At sunset, the bungey overcame the weight of the panel and it flipped to the east.

Stunningly simple.

[Bill McCarthy]

There are quite a number of ground source heat pump installations in the county using the trench system rather than a borehole. A near neighbour is very impressed with it - it was installed at build ten years ago and the floor is nice and warm. The council installed air source heat pump systems in outlying village council houses some years ago now but I hear it is expensive to run - the units are 18Kw. All stone built properties in the north can apply for free external cladding (paid for by the electricity companies) and many have taken it up but it is very fragile - rendering over 100mm insulating foam..
I have been pondering doing a DIY job - making a 10 sq/meter slab of concrete, painted mat black, contained within a heavily insulated “box” and covered with 1sq/meter double glazing panels (which I have handy) . The thing is, do I make 50mm air passages in the concrete for a “hot air” system or incorporate copper tubing in it for hot water. I have plenty of room, facing south for a curved array even. What prompted me was how hot the dashboard of the car gets when sitting in the sun. What do they say - heat capture can be 1Kw per sq/ meter..

By the way - I hadn’t intended to put the solar panels on the roof, but mounted about 5ft off the deck on a central column to make it sun following and easy to clean, or brush snow off it.
I’m interested in this heat exchange tube thingy - could we get a piccy per chance ?

[nallen]

The council installed air source heat pump systems in outlying village council houses some years ago now but I hear it is expensive to run - the units are 18Kw.

That sounds like a spectacularly stupid thing to have done. Air-source heat pumps really only work properly when combined with very good insulation and preferably underfloor heating - if you try to generate the heat required for radiators you're working well outside their optimum efficiency. (Our new-build house is built to the latest Danish energy-efficiency requirements; we've got an air-source heat pump, which also ventilates the house -- we've just got the first quarter's electricity bill which was encouragingly low, and the solar panels that are going up next month should cover the energy.)

[OCB]

There is one brand of fan assisted radiator that is designed to work at optimum efficiency for the low/limited range that heat pumps generate.

Never tried them, but could be an option for those who are limited due to listed building status (or in my case, wife who point blank refuses to have underfloor heating)

[OCB]

@Bill McCarthy - I haven’t seen this system, but I think I can figure out how it would work. Would be happier if someone had a link though!

Like old fashioned wrought iron gates that used to adorn “stately homes”, you’d probably have to get your weight and balance spot on - otherwise the forces require to shift panels (and keep in place given wind force) could mess things up . Not to mention that I doubt the insolation per m2 where you are versus California are maybe a bit different.

I did follow a “Creative Commons” project where some gent did use an Arduino or R.Pi and photo sensitive cell + stepping motor to do sun tracking. It was jerky as hell, got confused by cloud - and apart from being an interesting back yard engineering project, kinda useless.

A Raspberry Pi, programmed with where Mr Sunshine will be for your latitude and longitude for the coming years, and hooked up to a low cost geared motor would do the trick IMHO.

[Flyin'Dutch']

wife who point blank refuses to have underfloor heating

Interesting.

What is the rationale for that point of view?