Circular reasoning (Rolfe's solar energy system)

[Gadget Geek]

https://www.moneysavingexpert.com/utilities/free-solar-panels/

 

[Bam Bam]

I find the cognitive dissonance jarring.

On the one hand we have governments signing up to pledges to limit warming to 2 degrees and ideally 1.5 degrees.

And the fact that solar panels are now so cheap they can be used instead of fences or roof tiles.

Meanwhile there are new houses being built near me which have gas heating being installed (at great expense to run the gas underground to them). It would probably be no more expensive to install and run a heat pump, so it is just laziness and ignorance that are getting in the way.

Relevant to this thread, there will be a handful of solar panels installed inline on a small part of a roof, maybe 30-50% of potential roof space. This essentially blocks future additional panels which would have to be applied in a different fashion on top of the roof.

In some cases there are large South-facing roofs with no panels on at all.

There is a plan to build a massive solar farm outside Oxford, facing much opposition. It is a good idea, IMHO. However, the complaints are 'they shouldn't go in fields they should go on roofs and above car parks.' Well we aren't putting them on bloody roofs even when there is scaffolding up there and they cost the same amount as roofing tiles.

Completely disjointed policy making.

 

[JohnV6]

Fully agree. It is the same here.

 

[T1 Terry]

This is the solar/battery farm roughly a km away from our place

That cleared block is where the battery plant has been installed over the last 12 mths

Mannum BESS | Epic Energy

Epic Energy is expanding its Mannum Energy Park to include a Battery Energy Storage System (BESS) that will support South Australia’s energy security.

epicenergy.com.au

Threr is another large solar farm near Murray Bridge, about 30 kms away, but I can't find a link to it.
This one is near The Bend motor racing complex, about 60 kms away Tailem Bend Solar Project Stage One - Vena Energy

There are other solar farms in the area, all within a 30 km radius, so solar farms are big business over here.

The state is dotted with solar farms and battery farms and provides peak power to the eastern states. We also have massive wind farms, so a lot of cheap energy .... and probably the highest priced residential power in Australia ........ Nearly every roof is covered in solar panels, yet they pay a few cents per Kwh fed into the grid .... and they wonder why people like myself are planning to go totally off grid .......

T1 Terry

 

[Rolfe]

Politicians aren't necessarily the brightest crayons in the box.

Can the farmland under the panels still be used for grazing or other purposes? Or was it unproductive land to start with? The adjacent fields look as if they are cultivated.

 

[SimonS]

Politicians aren't necessarily the brightest crayons in the box.

Nor are some builders. There is an estate that was built in Ayr about three years ago. All 27 of the houses have solar panels. 6 of them face north west and 4 face north.

 

[T1 Terry]

Politicians aren't necessarily the brightest crayons in the box.

Can the farmland under the panels still be used for grazing or other purposes? Or was it unproductive land to start with? The adjacent fields look as if they are cultivated.

In the Mannum solar farm case, water is the big cost and without it, they are growing rocks. This land would have been sheep grazing previously, the panels are close to the ground to stay out of the high winds and the panels track east west, so not suitable for grazing really. By selling that land, they get to invest in pasture improvement and get the rain run off for free. The funny half round shed looking things are feed troughs for a piggery ...... fortunately the wind does come from that direction to where we are, just about centre right of the photo but maybe 4 or 5 blocks out of shot.

This is a Google shot around 2 yrs old, the arial shot gives a better idea of the size, the red spot in the corner is a 20ft shipping container, Mascott Cabinets is next door to make it easier to locate

T1 Terry

 

[Rolfe]

Nor are some builders. There is an estate that was built in Ayr about three years ago. All 27 of the houses have solar panels. 6 of them face north west and 4 face north.

Oh for crying out loud.

In the Mannum solar farm case, water is the big cost and without it, they are growing rocks. This land would have been sheep grazing previously, the panels are close to the ground to stay out of the high winds and the panels track east west, so not suitable for grazing really. By selling that land, they get to invest in pasture improvement and get the rain run off for free. The funny half round shed looking things are feed troughs for a piggery ...... fortunately the wind does come from that direction to where we are, just about centre right of the photo but maybe 4 or 5 blocks out of shot.

This is a Google shot around 2 yrs old, the arial shot gives a better idea of the size, the red spot in the corner is a 20ft shipping container, Mascott Cabinets is next door to make it easier to locate

T1 Terry

I suppose if it's only a small percentage of their land, it all works out. There are quite successful trials here where the panels are mounted a bit higher allowing sheep and cattle to graze underneath. I think they space them out a bit more too, so that the grass gets the sun as it moves. The animals seem to like to lie in the shade of the panels when it's hot.

 

[Gadget Geek]

It's called Agrivoltaics, and some crops prefer the shade of the panels and the panels are cooled by the water vapour the plants emit from photosynthesis.

 

[Bam Bam]

I suppose if it's only a small percentage of their land, it all works out. There are quite successful trials here where the panels are mounted a bit higher allowing sheep and cattle to graze underneath. I think they space them out a bit more too, so that the grass gets the sun as it moves. The animals seem to like to lie in the shade of the panels when it's hot.

Yes someone showed me around their solar field with sheep underneath.

The sheep shade under the panels and the grass grows well.

 

[johnb80]

It’s not a discursive point; it is simply arithmetic.

Agreed that's why I'm somewhat puzzled you don't seem to understand it.

 

[Bam Bam]

Nor are some builders. There is an estate that was built in Ayr about three years ago. All 27 of the houses have solar panels. 6 of them face north west and 4 face north.

Yeah, one of the houses in the nearby development has a single north-facing panel!

It must be a box-ticking exercise to meet the 'sustainability' regulations or something like that. Install a car charger, some loft insulation and a single solar panel and you're golden.

I'm not against North-facing panels by the way as they will still generate a little, but you need a lot of them to make up for the low density generation!

 

[SueH]

Completely disjointed policy making.

Yes, something I've long found annoying. New estates going up locally with not a panel in sight, my regualr rail trip to a nearby city passing plenty of those two panels surrounded by tiles, and where the fixed and inverter costs must be massive as a proportion of total cost..

I'd hoped the new government would have moved a bit quicker but the builders have obviously been bleating loudly again..

 

[T1 Terry]

Yes someone showed me around their solar field with sheep underneath.

The sheep shade under the panels and the grass grows well.

It would work well for fixed panels, but these tilt to almost 90° each way to keep the evening dust laden breeze from building up on the panels, lie flat when there are high winds or a cloudy day, but otherwise, track to around 45° each way ..... I can picture some mindless sheep being pinned under a panel as it tilted .... and someone would have to oversee the sheep's health etc ..... probably not a financially viable option in a country with so much free space.

Add to that, every 3 mths, a tractor with a spinning brush where a barrel mower would normally be, sprays detergent in front of the brush and fresh water behind it to rinse and the panels are at near the 90° mark, rows facing each other, so this thing can clean two rows with a simple turn around at the end. As the tractor sets up to do the next two rows, the cleaned rows go back on line. These panels are the height of the average person, so although the rows look close to each other, tilted face to face there is over 2.5 mtr between them, plenty for the tractor to drive up and down.

The output between a clean panel and panel with enough of a build up to show a white tinge, is over 5% improvement .... I'm guessing these are 550W panels by the size, that more than pays the cost of cleaning them when you have that many panels ......

I saw one solar farm where they tried goats to keep the weeds under control, stupid things either ate the wiring and killed them, or they climbed on top of the panels when they were flat enough for them not to slide off .... and did quite a bit of damage when they tried to climb on at too steep an angle or try to avoid sliding off as the angle changed ....

Love goats, but they are about as stupid as sheep .......

T1 Terry

The thing that makes no sense to me, is developers buying up good agricultural land, sub dividing it and filling it with houses that the rain water gutters near touch each out, a token patch of lawn, the rest is either roof tops, concrete driveways or bitumen roads.
They that complain that the area floods when it rains big time .... that is why it was prime agricultural land ....... It gets plenty of rain to water it There is no road network so they are caught for hrs at a time getting into the city to work, then back home again .... so they have to spend mega tax payer $$ building multi lane highways and rail networks .......
Why didn't they spend the big $$ first and biuld the houses outside the city prime food bowl land?

Now, all the good growing soil with good rainfall is covered in houses and only less optimal land is available for growing vegetables and grass for cattle ...... now they are panicking about food security and the cost of having to grow vegies in hydroponics converted shipping containers so it is fresh when it reaches the city markets ...... where were the brains trust when this nonsense started?

T1 Terry

 

[Gomev]

Yes, something I've long found annoying. New estates going up locally with not a panel in sight, my regualr rail trip to a nearby city passing plenty of those two panels surrounded by tiles, and where the fixed and inverter costs must be massive as a proportion of total cost..

I'd hoped the new government would have moved a bit quicker but the builders have obviously been bleating loudly again..

Not saying they aren't solar panels but could they be hot water panels as they often come in twos and look very similar. For example

 

[Anon70]

I find the cognitive dissonance jarring.

On the one hand we have governments signing up to pledges to limit warming to 2 degrees and ideally 1.5 degrees.

And the fact that solar panels are now so cheap they can be used instead of fences or roof tiles.

Meanwhile there are new houses being built near me which have gas heating being installed (at great expense to run the gas underground to them). It would probably be no more expensive to install and run a heat pump, so it is just laziness and ignorance that are getting in the way.

Relevant to this thread, there will be a handful of solar panels installed inline on a small part of a roof, maybe 30-50% of potential roof space. This essentially blocks future additional panels which would have to be applied in a different fashion on top of the roof.

In some cases there are large South-facing roofs with no panels on at all.

There is a plan to build a massive solar farm outside Oxford, facing much opposition. It is a good idea, IMHO. However, the complaints are 'they shouldn't go in fields they should go on roofs and above car parks.' Well we aren't putting them on bloody roofs even when there is scaffolding up there and they cost the same amount as roofing tiles.

Completely disjointed policy making.

In my experience all companies care about is profit so if you are a builder and a gas boiler manufacturer is looking to offload a few hundred boilers at a good price (because installing them in new builds is about to be banned) vs paying full whack for new heat pumps you will buy and install the gas boilers. As a builder you don't give a stuff what it costs a home owner to heat the property.

Similar reasoning as to why fibre broadband was not run to every new build in the last 20 years. Lets keep installing the old cheaper tech (that we probably have lots of stock of)

And the same reasoning as most ICE car purchasers have now, as the initial purchase price of the ICE car is lower than an EV despite the environmental and running cost benefits.

 

[Berkofix]

Had an issue like this on my EV/PV/House Battery system.

Inside = Eddi and Zappi feeds in main consumer unit but after RS485/Inverter CT clamp.
Outside = Eddi and Zappi feeds moved to after the grid smart meter but before the RS485/Inverter CT clamp or consumer unit.

Essentially placing the Zappi & Eddi "Inside" inverter/house batteries influence means the batteries can get drained. Once the RS485/Inverter clamp detects a flow it "wants" to service it.

Strategies around this are: Setting a 50/100W export threshold margin on the Eddi (this worked well, but not so much on the Zappi), charging the house batteries off the grid at night blocks draining (Works well, a battery is either charging or discharging but not both).

However, using Octopus Intelligent Go meant the Zappi might charge within the period of 11:30pm to 11am. In this case the Zappi would suck the 10kWh house battery dry if running after 5:30am (the usual stop point for cheap rate house battery charging.)

Looking on the Myenergi forums you can move the Eddi and Zappi "Outside" the inverter/house batteries influence. This has worked well in the winter. With practically no excess generation all one needs is Octopus Intelligent Go to kick off the Zappi car charging. Eddi and the house batteries charge on a fixed 11:30pm to 5:30am cycle. When there is export to grid the Eddi is good to pick it up as it can run on very low amounts.

Presently I am scratching my head once again. The minimum charge allowed by the Zappi is 1.4kW. During the spring/summer I might see that but its unlikely to be consistent. If I allow the Zappi to kick off on a 50% ECO+ it will draw 700W from the grid and 700W from the solar PV.

https://support.myenergi.com/hc/en-gb/articles/360020720298-What-are-the-zappi-charging-modes

I can plug in the granny charger as that comes off the house battery and runs at 1.9kW (MG5 app). But its a bit clunky and pedestrian. In theory this would allow me to rebalance the car battery, but it has done so few miles its not an issue yet.

I imagine I will move the Zappi back to the inner consumer unit but its inelegant and yes the batteries are liable for discharge outside their charging period at night. I could buy a changeover switch, to swap between the 2 x 32amp feeds but again its a bit marginal.

BTW House batteries charged at 30amps in the winter, or 1amp in the summer to block drainage and reduce degradation. Have to say getting the MG5 EV and onto Octopus Intelligent Go has been a game changer for winter leccy.

 

[Rolfe]

I have been mainly charging the car between 11.30 and 5.30 using the Zappi's schedule. Works fine, because the home battery is either empty or charging during that time.

As I understand it, Octopus only require you to do one Smart charge a month, which isn't hard to organise. Simply activate the charge after 11.30 and say you want the car by 5.30. We'll see if they say anything.

 

[johnb80]

As I understand it, Octopus only require you to do one Smart charge a month, which isn't hard to organise. Simply activate the charge after 11.30 and say you want the car by 5.30. We'll see if they say anything.

Be careful, the resident grass may be watching

 

[Everest]

How, technically, does Zappi integrate with a solar + battery system? From what you are saying it doesn't seem to discriminate between solar generated vs. battery power coming from your inverter.