Where should solar panels be placed

[David George 1Participant @davidgeorge1]

I was listening to a report that solar panels should be placed on every new roof house or commercial building and every car park should be used as well by having the panels mounted on poles so cars can be parked underneath them and use the power to charge the cars.

What do you think

David George

[duncan webster 1Participant @duncanwebster1]

Yes to on every building roof. Not sure about car parks, the supporting structure would have to be large span, can’t have lots of legs, so depends on the economics. I suspect you’d have to park under a solar panel for a long time to charge a car.

[Roderick JenkinsParticipant @roderickjenkins93242]

I think France has mandated that all new car parks around places like supermarkets should be built with solar panel roofs.  I don’t think that the idea was to specifically use the electricity generated to charge the cars parked underneath but to utilise the acreage (hectareage? ) for dual use rather than stealing agricultural land for solar farms.  Seems like a good idea to me and keeps the sun or rain off you car.

Rod

[Robert Atkinson 2Participant @robertatkinson2]

The bigger issue at the moment is the electrical infrastructure can’t cope with the existing and planned solar generation. We need more power distribution capacity and some means of energy storage to make best use of solar.

[duncan webster 1Participant @duncanwebster1]

Well if it’s over a car park it is likely there will be cars to charge, so distribution could be less of an issue. They could also have some kind of system for storing coldness (dry ice?) to run the freezers and to heat the supermart in winter (although the solar panels will produce less in winter)

[Mark RandParticipant @markrand96270]

It’s almost unpardonable now to build any new commercial or domestic building without solar panels on the roof unless there are shading or orientation reasons that would severely limit the output. During construction is the cheapest possible time to install solar panels. Specific in roof solar panels (as opposed to in roof frames with general purpose panels mounted in them or retrofitted panels on supports over an existing roof) are a small, but growing sector of the market, but at today’s prices are only 50% more expensive per square metre than the cheapest clay roof tiles.

In my town, on what was the Rugby Radio Station, an estate of 6,200 houses is being built. That would only generate about 25-35MW admittedly, but that is probably less than the installed capacity required for such an estate. Any house owner with two or more neurons to rub together would install an inverter and batteries if they weren’t already built in, meaning that typical grid loading would be significantly less for much of the year.

Similarly, car parks will normally have EV chargers, shops or electrified train lines associated with them or very close to them, so solar power installations will reduce, rather than increase MV and HV capacity requirements for much of the year.

Interestingly, my local hospital has recently added solar panels to every available bit of roof that’s pointing in about the right directions. Good for them. 😀

[Robert Atkinson 2Participant @robertatkinson2]

The problem with network capacity is the ability to accept power from solar and wind not supply power. While houses and chargers can accept power locally, generally the demand is higher in the evenings when solar output is less. Even th supermarket car park is unlikey to have enough consumers to accept he power generated at peak sunlight.

[File HandleParticipant @filehandle]

There has been a lack of joined up thinking. Often Solar and wind farms are paid not to produce electricity because the “grid” can’t cope with it. It would make sense to use this free electricity to electrolyse water to produce hydrogen (and oxygen) which can be stored for later use. Spreading out the generation make sense as it should reduce the load on the distribution grid. batteries keep being suggested as a storage solution, but is there sufficient raw materials for this to be a long term solution? it is obvious why Smart meters are being pushed, but I can’t see them matching demand with supply unless they are going to use their built in off switches.

[alan ord 2Participant @alanord2]

Put solar panels over reservoirs. Dead space and it will help reduce evaporation.

Alan.

[File Handle]

On File Handle Said:

There has been a lack of joined up thinking. Often Solar and wind farms are paid not to produce electricity because the “grid” can’t cope with it

 

Please find a single instance where that has been the case…

 

On Robert Atkinson 2 Said:

The problem with network capacity is the ability to accept power from solar and wind not supply power. While houses and chargers can accept power locally, generally the demand is higher in the evenings when solar output is less. Even th supermarket car park is unlikey to have enough consumers to accept he power generated at peak sunlight.

Sorry, that’s simply not the case.

The total capacity of such schemes would be well within the capacity of the local MV and HV grid capacity and the grid as a whole can accept power readily. If the local infrastructure can supply a given amount of power, then it can accept the exactly same net amount of power. The HV grid, attached generators and Dinorwig cope readily with multi GW sized step changes when power stations have multiple unit or transformer trips, so the rate of change from solar installations is trivial in comparison. In the case of the supermarket car park, any supermarket which invested in such a scheme would also invest in a commercial storage plant, purely to reduce the cost of grid supply. Current systems run at 2.8MWh per 40 foot container (GivEnergy in this instance, other suppliers are available). This means that output and supply can be used by the business over a longer period and that excess output can be exported at a rate that the existing infrastructure can maintain and when the prices are best for the business. Given the desire to cease the sale of IC engined passenger cars by 2030 (or 2035 according to the current idiot in charge), supermarket car parks are also going to have a lot more chargers…

[Robert Atkinson 2Participant @robertatkinson2]

So why are wind farms and solar farms being delayed due to lack of grid capacity?
The storage you mention is battery based and expensive.

[Mark RandParticipant @markrand96270]

Wind farms and solar farms are almost by definition not in urbanised areas! They are in areas which do not have any great MV power infrastructure. Car parks, houses and commercial buildings are always in areas with well developed LV and MV infrastructure or attached loads which are commensurate with the possible solar generation capacity…

The storage I mention has moderately high capital cost, but is a small part of the overall investment. Per MWh, it’s less expensive than EV battery packs and can have an ROI of 4-5 years when used as described. I know I need to at least double my current 8.2kWh of battery storage 🙂

[duncan webster 1Participant @duncanwebster1]

Of course there’s no joined up thinking, UK government is in charge. Now if you wanted a new translation of Ovid we’d be world beating

[egaParticipant @ega]

Ovid: “Nothing over sixpence on the classical bookshelf” as the crossword setter has it!

My house has a north/south orientation and I have always thought that solar panels would be uneconomic but perhaps they may become so.

[File HandleParticipant @filehandle]

Floating solar farms are being worked upon. Artificial leaves that use a form of photosynthesis to produce hydrocarbons. This idea has been around for some time, just needs developing.

[SamsarandaParticipant @samsaranda]

A recent local news item on TV featured our local hospital in Eastbourne that has installed solar panels above the staff car park, it was a sizeable installation capable of generating a considerable amount of electrical power, Eastbourne is known as the sunniest resort in the UK so a no-brainer. Coupled with the Solar development the hospital has installed Heat Pumps to green the process of generating hot water in the building. The news report was at great pains to point out that the project was not funded by NHS funds but specific government budgets that enable organisations to reduce their energy usage footprint.  Dave W

[Michael GilliganParticipant @michaelgilligan61133]

Please forgive the slight digression … but it was relevant to my own investigation into the financial viability of domestic solar panels [as per ega’s recent post].

The not-so-small matter of ‘Standing Charges’ is under investigation by Ofgem … which currently has an active “Call for input” from the public:

eMail : StandingCharges@ofgem.gov.uk

Look at your tariff and tell them what you think, whilst the opportunity is available.

MichaelG.

[Rod RenshawParticipant @rodrenshaw28584]

30 years ago my cousin, who lived and worked in Phoenix in Arizona, had a choice when he went to work: he could park his car in the open air car park where it got very hot and the paint faded, for free, or he could park under a special built shaded roof area of he car park, which cost money. So perhaps solar panels over car parks are not impractical.

[gerry maddenParticipant @gerrymadden53711]

My house faces south and has a near perfect 35 deg sloping roof so 10 years ago I fitted a 7.5kWh pv system. For 9 of those years I have generated around 12% more power than the government predictions. Is that one of the benefits of global warming?!… I dont know, but what I do know is that the system covered all of its costs, including interest on capital etc, with 6 years. Now its all money in the bank for me and cheap electricity into the grid which will be swallowed up locally I’m sure. Batteries were not considered economic at the time I made my investment so I didn’t fit any. (They might be now, I dont know.)

It therefore appears to me that solar panels, especially with a storage system, can only be a benefit. One other interesting thing, particularly for us workshop-inclined chaps, is that that some domestic inverters are now available that will output single and three-phase power. I assume the latter is intended for fast car-charging, but I can think of other uses :).

Gerry

[Michael GilliganParticipant @michaelgilligan61133]

In stark contrast to Gerry’s enviable situation … My ‘reality-check’ came with the quote of more than £18k for a battery-backed system with ten roof-integrated panels.

 

I won’t go into the details, but show here a snapshot from the overview:

 

Given that I presently pay £55 per calendar month for all the Electricity that I use [the central heating being oil-fired] … this is simply not an economically viable proposition.

The proposal was a masterpiece of wishful-thinking !

MichaelG.

[Mark RandParticipant @markrand96270]

Get multiple quotes Michael.

[gerry maddenParticipant @gerrymadden53711]

7.5kWh ???  Even I didn’t spot the deliberate error in my earlier post ! That should of course been 7.5kW system.

Gerry

[Roderick JenkinsParticipant @roderickjenkins93242]

About this time last year we had 16 panels installed (on the roof not integrated) 7 facing ESE and 9 SSW together with a 5kWh battery.  Total cost 10k£ from a local company.

This year to date we have:

Load 4.7MWh

PV generated 6.5MWh

Imported 1.9MWh

Exported 2.7MWh

We live on the Dorset coast half a mile from the beach.

When one is considering a payback time I guess it depends how long one expects to live 🙂

Rod

[Mark Rand]

On Mark Rand Said:

Get multiple quotes Michael.

It wouldn’t make any real difference to the logic, Mark

… unless someone was almost giving-away a system

My Electricity costs £660 per year.

If I reduced my nett consumption to zero, the Standing Charge would still be £227 and the SEG tariffs are unpredictable beyond the current year.

 

MichaelG.

.

 

[BazyleParticipant @bazyle]

Thanks for the information MG and RJ especially the graph showing relative generation by month but one HUGE factor missing. Mentioning 5, ten, fifty panels is meaningless as they might be 5W each or 500W per panel.
What would be useful is actual output per rated kW per day or week over the year and for different practical angles. Like I have a flat garage roof that could take say ‘4 panels’ and what I need is power in mid winter knot mid summer. Professionally installed MCS approved  grid connected is unlikely to be financially viable nowadays but an off grid ELV set up does have somme possibilities.

[Author]

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