Solar ... In the news

Coastalwatch

Martyn1981 wrote: »

Also coming at it from a supply side (rather than export), maybe some sort of faster EV charging potential in the future ..... not really sure about that bit as I assume we are already good for 20-25kW(?).

Oh, and one other bit, I think any batteries than can discharge at a rate greater than 3.68kW (PW II is 5kW & 7kW briefly) also need DNO approval.

Yes, interesting points and as usual the plot thickens as there seldom seems to be a straightforward answer. On the one hand is the desire to have a fast charging ability, certainly necessary when on long journeys, but perhaps questionable domestically as once home time is generally available to charge at a lesser rate. For those of us fortunate enough to be home daytime with the EV happily charging off solar it's not a problem, but for those out at work all day then overnight on E7 seems the only alternative until home storage of suitable proportions and cost become available. Domestically batteries of circa 4-12kWh may suffice but bring an EV into the mix and we're perhaps needing upwards of 50 kWh's!

Now something on that scale would be really useful!

If need be we could run a whole week domestically off of it.

To date the largest I've come across is 20.5 kW retailing at around £11k, so it looks like it's going to be sometime before we shall be "investing" any further.

michaels

pile-o-stone wrote: »

I agree with this, the standard configuration used to be 16x 250w panels to give a 4kW array. The most efficient panel I can find currently is 370w and the panels are roughly the same size as the old 250w ones. This gives you an array of 16 x 370 = 5920 w. If you're looking to add a conservatory on the back ond use the new transparent pv panels (the ones I have been looking at give good transparency at 250w), you could add 8 panels to give a further 2kW of generation. A reasonably sized semi could be generating almost 8kW.

The stumbling block will be the DNO. Increasingly they seem to be trying to block arrays over 3.68kW. They won't even look at your application unless you pay a £300 fee and often it results in a demand to 'strengthen the grid' that costs thousands.

I was looking at adding a lean-to oak pergola with transparent pv panels (2 banks of 6 panels @250w = 3kW). The DNO said I'd have to pay £1500 to strengthen the grid. With no Fits and an additional £1500, they are just not cost effective. I might just put up the pergola without panels and look at adding them at some point in the future if I win the lottery or something.

For anyone who is interested, the details on the transparent panels are here:
http://www.bisol.com/images/Datasheets/EN/BISOL_Lumina_BMO_BSO_BLO_EN.pdf

p.s. I have also considered having the 3kw panels 'off-grid' and use the £1500 DNO fee to buy batteries, but I don't know what I'd then do with the power? If anyone has any ideas, I'd appreciate the input. All I can think of is running a rainwater harvesting pump for toilets and garden irrigation, garden lights and perhaps a DC freezer to hold the produce from our allotment.

We have 4kw of panels that max out at about the inverter rating of 3.6kwh facing west. I reckon in theory we could add the same amount of panels facing East using the same inverter and just dump about 10% of generation daily at peak. What would the DNO say to this? Problem is that we have FIT on the existing panels so I don't suppose we could just add more panels through the existing inverter, the utility company would probably notice if our generation increased by 30%....

Seems like it would take a big battery to store typical summer day generation but given our summer import seems to be 15kwh per day we would at least be able to use most of the power stored....

Martyn1981

pile-o-stone wrote: »

For anyone who is interested, the details on the transparent panels are here:
http://www.bisol.com/images/Datasheets/EN/BISOL_Lumina_BMO_BSO_BLO_EN.pdf

I'm interested, and thanks. I had no idea they'd reached that level of efficiency. Take your eye of the ball for one second and PV leaves you behind again, wow.

I like the table on here showing the level of transparency, so you choose the panels you want:

BISOL Lumina series (monocrystalline)

Thinking about it for a pergola, when it's cold and dark you stay in, and when it's hot and sunny you put up a sunshade, so something like this is fascinating.

Also for a DIY greenhouse they could make great sense as the plants suffer from full sunlight (and heat) so reducing the total amount that gets through is advantageous. Perhaps a monopitch greenhouse, all south(ish) facing but with 30-50% of the light blocked.

PV no limits. Cool!

pile-o-stone

michaels wrote: »

We have 4kw of panels that max out at about the inverter rating of 3.6kwh facing west. I reckon in theory we could add the same amount of panels facing East using the same inverter and just dump about 10% of generation daily at peak. What would the DNO say to this? Problem is that we have FIT on the existing panels so I don't suppose we could just add more panels through the existing inverter, the utility company would probably notice if our generation increased by 30%....

Seems like it would take a big battery to store typical summer day generation but given our summer import seems to be 15kwh per day we would at least be able to use most of the power stored....

The DNO doesn't care about the DC generation of your solar panels, as long at the output to the grid from the inverter is 3.68. The problem you'd have is that inverters only allow a certain amount of 'overclocking' (for want of a better word) and they have a maximum DC input. I doubt you could put 8kW of solar into a 3.68 inverter without blowing it up Your inverter should have a max input value printed on the side or maybe in the user manual.

You're correct about your FiTs stopping you from adding panels to the existing inverter. If you added more panels, they would have to be attached to a new inverter that doesn't feed through the FiT meter. We added 1.8kW of extra panels and these go to a separate 1.5kW inverter. Extensions don't qualify for FiT payments, so these don't go through a meter (though you could add one for your own info if required).

pile-o-stone

Martyn1981 wrote: »

I'm interested, and thanks. I had no idea they'd reached that level of efficiency. Take your eye of the ball for one second and PV leaves you behind again, wow.

I like the table on here showing the level of transparency, so you choose the panels you want:

BISOL Lumina series (monocrystalline)

Thinking about it for a pergola, when it's cold and dark you stay in, and when it's hot and sunny you put up a sunshade, so something like this is fascinating.

That was my thinking. I like sitting on our patio when it's sunny, but I dislike eating at the table in full sun and so always put up the brolly. A solar pergola above the patio, even if it just covered the table would make perfect sense.

This company manufactures them: http://en.irfts.com/irfts-shadow-solar/

you can buy them in the UK from bimble solar.

Martyn1981 wrote: »

Also for a DIY greenhouse they could make great sense as the plants suffer from full sunlight (and heat) so reducing the total amount that gets through is advantageous. Perhaps a monopitch greenhouse, all south(ish) facing but with 30-50% of the light blocked.

PV no limits. Cool!

I also considered this as it wouldn't make sense for me to pay £1500 to 'strengthen the grid' to just add 3kW on a pergola when the DNO said I could go upto a max of 10kW. I was therefore pondering the pergola and also adding a passive greenhouse further down the garden with maybe another couple of kW of transparent solar on it.

The following design could have the transparent solar on the top row of glass, which would shade some of the powerful summer sun, but wouldn't really block winter sun as it's much lower in the sky. I could also change the design and instead of the downward sloping roof at the back of the greenhouse, have the slope continue upwards and attach a couple of 370w panels in a landscape orientation at the very top. They obviously wouldn't let light through, but as they're so high up, it wouldn't matter too much.



p.s. if anyone is interested in this sort of greenhouse design, it's a passive greenhouse that is heavily insulated in the floor and northern wall, with either partial glazing and insulation or just insulation on the east and west walls. This extends the growing season deep into the autumn and early into the spring months. Loads of details here:
https://www.motherearthnews.com/organic-gardening/how-to-design-a-year-round-solar-greenhouse-zbcz1502

Martyn1981

Petition launched urging government action on new housing and solar PV

The petition seeks to trigger a debate in parliament over whether or not the measure could be enacted, and how it would work in practice, mentioning how there is currently no supporting legislature that specifies the addition of solar panels to new build developments.

With the government having last year outlined plans to build 300,000 new homes each year, the petition argues that if just half those were built with standard solar PV installs, it would be enough to increase the country’s solar generation capacity by 5% annually.

It seeks legislation to require house builders to install a “meaningful amount” of solar PV, with firms needing to justify their decisions based on a lifetime economic return calculation reached using a national model.

There would, however, be exemptions for properties developed in areas of high shading or low irradiance, as well as recommendations on how to install solar on homes with shared roofs.

Martyn1981

The Aussie state of Victoria is to subsidise 650,000 domestic PV installs over the next 10yrs to bring the number up to about 1,000,000. For context there about 800,000 installs in the UK.

Victorian Labor offers half-priced solar panels for homeowners in $1.24bn pledge

Coastalwatch

Martyn1981 wrote: »

Petition launched urging government action on new housing and solar PV

Thanks for posting Mart, have signed the petition and also written to my MP urging her to support renewable energy wherever possible.
Wonder what sort of reply I'll get, apart from the usual automated response that is!

Martyn1981

Coastalwatch wrote: »

Thanks for posting Mart, have signed the petition and also written to my MP urging her to support renewable energy wherever possible.
Wonder what sort of reply I'll get, apart from the usual automated response that is!

The news today shows huge support for solar:

Majority of UK public want to install solar panels, poll finds

More than half of the British public would install solar panels and home batteries to tackle climate change if there was greater assistance from the government, polling has found.

While many have already made their home more energy efficient, 62% said they wanted to fit solar and a surprisingly high 60% would buy an energy storage device such as .

An even greater number !!!8211; 71% !!!8211; would join a local energy scheme such as a community windfarm or solar panel collective, according to the YouGov survey.

The government line tends to be simple - that there is only so much money, and PV and on-shore wind should now be looking after themselves.

However, that policy flies in the face of their support for new nuclear, since it's already had 60yrs of support, and given the vast volume of generation, then that also means a vast amount of subsidy v's the relatively small amount of generation that receives subsidy support for PV and on-shore wind.

So far less money in, has delivered faster cost reductions for RE.

I have no problem with subsidies being reduced, nor removed when appropriate, but chopping 4p/kWh support for PV, to be paid to UK households in 2019 makes no sense when new nuclear is to get 5-6p/kWh of support in 10yrs time (when PV will surely be subsidy free) and that money will leave the UK economy as it'll be paid to the Chinese and French governments (EDF is 85% state owned).

It's also clear that the PV industry is struggling, not thriving, so the government can hardly point to any factors that support their position.

I think 4p FiT (v's the 5-6p foe nuclear), combined with an ending of the MIP (EU minimum import price for PV), and perhaps some sort of national policy on storage, would allow the PV industry to bounce back and the 'cost' to the subsidy pot would still be tiny:-

1,000,0000 new PV installs getting that 4p on 4,000kWh's pa [in reality they wouldn't all get 4p as the rate would drop over time, but lets leave it high for now] would result in £160m pa in subsidies for 20yrs, v's the £1.3bn pa that HPC will get for 35yrs.

Yes, HPC will generate much more leccy, but that doesn't change the unit subsidy which is still higher (6p v's 4p), and the subsidy pot's ability to fund a vastly greater amount of generation.

Martyn1981

Some news on higher efficiency PV using perovskite, and on the same subject, Germany is to fund research for perovskite. So 30%+ PV could be on its way next decade doubling the capacity from a given roof/area. I'd guess that a doubling of capacity will result in only a 50% increase in cost of install, and expect costs to keep falling in real terms too.

Should also be excellent news for PV farms as they'll get twice the generation for the same land, labour, racking, transport costs.

Researchers propose doubling today’s solar panel efficiency using two weird tricks

Oxford PV awarded €2.8 million German grant to ready perovskite-silicon solar cell production