GigaFactory

It would appear that the controllers that work with solar+battery installations can also include the capacity of appropriate electric vehicles in their management capabilities. You can program them for desired time slots, so if you need the car at dark 'o' clock of the night it'll still have its charge in it.

I've been spending a little time trying to do the sums for solar panels and batteries. The Shed has got 33m^2 of almost flat roof that would be ideal for a solar installation. There's room outside it for battery banks and it's got a 4 core 16mm^2 cable going back to the house, even though I never got around to getting 3ph run in. Average power consumption is about 1kW.

Trouble is, that I can't make the sums add up. Having the money is no problem at all, but it appears that Keeping the money invested in funds generates a higher return. This is causing me great annoyance, because I'd really like to make use of that nice roof.

The shed is at **LINK** Note that their web site has an expired certificate. This isn't a hacker site. I'm vastly amused that I got that location though!

^^^^

Edit to add that it looks like the certificate error that my browser saw was a temporary hiccough.

I was doing the same math recently. The only way it might work out without the pittance from passing spare current back to the grid (no SMETS here) is with ownership of an electric car, lousy rural leccy costs and assumptions re how much leccy prices might go up. Even then if one starts to factor in replacement inverters and paying someone to clan the panels every few years, I’d need some better guarantee of lifespan than statistics suggest for me...

pgk

I've had my solar panels for 10 years now and with the original high feed in tariff payments it's been a very good investment. BUT, like pgk, when you do the sums now it's very difficult to make the numbers add up. With next to no FIT nowadays the payback time based on what you save on energy from the grid is going to be very long. I would love to have battery storage for the approximately 55% I feed back to the grid but current costs make it a non starter.

Using an electric vehicle as the storage part of a system could be an option, me being retired, the car spends most of its time on the drive during the day so would be available when the generation is at its highest. I can't see me getting an EV in the near future though so most of this is just wishful thinking.

Peter

Climate change: Time running out to stop catastrophe! sez climate chief

https://www.bbc.co.uk/news/uk-58132939

sooo.... how many reservoirs are we constructing before time runs out?

how many trees are being planted to make life tolerable as we move around outside... before time runs out??

on the other hand...

how fast are they trying to get you to buy stuff like electric cars

how fast are your power bills going up

yup

time is running out, it's the big time-is-running-out-buy-stuff-sale

Most people don't even realise that its going on all around them 24/7

This is a pile of seaweed ripped up by a trawler near dunbar, tons of healthy seaweed in a 300 yard strip

The rest of that beach is clean sand

Habitat annihilation to put a packet of fish fingers into a fridge near you

yup

its a climate emergency, now buy our approved fish fingers

Edited By Ady1 on 08/08/2021 07:54:09

.

Upon which subject, there was a good piece in the Washington Post … which linked to this:

**LINK**

https://www.metoffice.gov.uk/weather/learn-about/weather/oceans/amoc

… The likely date of AMOC shutting-down is reckoned to be getting closer.

MichaelG.

Combining solar panels with this might be useful?

Vehicle-to-grid

It seems there just isn’t enough investment in this type of thing at the moment. And letting energy companies get away with paying only a tiny fraction of of what they charge you when you’re putting energy back is scandalous.

I agree with much of the sentiments above, it does feel like individual efforts cannot pay unless subsidised, and that often looks like the government is subsidising the comfortable classes whilst bemoaning those who can't pay, which is divisive.

The only way to make your sums add up is to buy shares in a developing company with a good chance of success, i.e. to gamble, that's not an easy choice for most people as there will be losers.

There is no easy answer.

There was , but as usual , poor management in the later years destroyed the idea.

Bought by our 'parents' , British Steel, Rail. Transport, Gas, Sugar , Motor Corp, CEGB ,Aerospace, all sold for a pittance.,instead of sacking the management.

Anyone have a clear description of dynamic containment and the principles? From a quick search there is a lot of high level stuff littered with power industry abbreviations but I couldn't find anything that gives a clear explanation? What I take from it is as follows but I may not have properly understood!

Dynamic Containment (DC) is a means of maintaining the grid at its nominal 50hz within the specified limits. As load increases according to generating capacity when load exceeds capacity frequency drops - think generator and you apply a large instantaneous load, frequency drops until the engine governor reacts and applies more fuel to bring the speed back up and in the case where where load suddenly reduces the frequency rises until the engine governor takes fuel off to reduce the speed. DC therefore is a means of load balancing by bringing in additional capacity either to deliver or accept load. Termed low frequency (LF) where power needs to be delivered and high frequency (LF) where power need to be absorbed to maintain grid frequency at 50hz. Good so far? The frequency can therefore be maintained by switching in and out assets to deliver (LFDC) or absorb (HFDC) very quickly.

So to archive the objective there needs to be assets available to either provide or absorb power. These assets are controlled by power companies (PC) and with regard to DC and the descriptions seem to be battery based?

Commercially the PC will bid on a future basis submitting their bids on Tuesday between 7.00 and 10.00 am for LF (supply) or HF (absorption) or both to the grid, the week ahead being split into 24hr blocks (contracts) The grid accept for this transient use there is a premium to be paid (price advantage) to the PC. I think the minimum capacity is 1mW and maximum 50mW. However non delivery of bid capacity will result in penalty - financial incentive to deliver.

I think that is the big picture? Digging deeper the PC will sign up assets (potentially you and your mobile battery - EV) to make up their capacity to support their bids. In order to be confident they can deliver the capacity bid for, obviously they need a buffer in their pocket of more capacity than they need as if they under deliver or fail to deliver they will be penalised.

Is that how it works?

If so the PC either needs a portfolio of fixed and mobile batteries in order to be confident during the 24hr period there will always be capacity plugged in to meet the obligation. I am not sure how that works when filtered down to the micro level - the individual EV owner. Initially I guess where there will be relatively few participating EV's you may be contracted to be connected to the grid somewhere at certain times of the day? As the available assets increase it may become less restrictive. However as the principle is competitive bidding to keep costs reasonable for the grid, as more capacity becomes available the bid price achieved by PC will drop and hence the premium paid to the EV owner will also reduce. Bit like the current solar panel situation where the generous feed in tariffs were put in place originally to encourage house owners to participate but now with growing capacity it is no longer necessary. In fact DC would make more sense to be concentrated on solar panels with battery storage, as a baseline will be much easier to predict with respect to state of charge and the batteries will always be connected as opposed to the mobile assets. I would bet though if you want maximum benefit from EV to grid, get in at the beginning because the benefit is bound to reduce with time.

Paul.

Seeing that batteries and therefore electric vehicles are Direct Current, how do they connect to a grid which is Alternating Current. Not only will the current have to be converted to AC it will have to be in phase as well

Roy

No Problem, this is exactly how a Solar PV sysytem works with a grid tied inverter. It changes the DC to AC and sychronises the frequency and phasing.

Peter

Well reading about Dynamic Containment made my head spin. The information on the web seems mainly focussed on managing the facility as a paying service rather than the technology behind it. It seems to one of several methods intended to manage energy from multiple suppliers rather than any particular generating method.

I don't understand it either! However, reading between the lines, I think DC is a contracted service allowing a provider to raise or lower the output frequency in order to manage energy in or out. I visualise it working the other way round from Paul, ie dropping frequency reduces power output, or accepts power back, whilst increasing frequency pushes more power out. Otherwise as he says.

Imagine two steam turbine generators connected to a grid. If one of them drops frequency the other will feed power into it and drive it's generators backwards faster; thus the low frequency station 'sees' a reduced load and burns less fuel. On the other side of the grid the other power station at normal frequency 'sees' an increased load and burns more fuel. A third source coming suddenly on line might be ultra-cheap electricity from a wind-farm, which it can 'sell' to the grid by raising it's output frequency so that other power stations on the grid work less hard. The overall effect is to balance the load whilst giving priority to cheap sources. Would be done on a grid supporting many thousands of generators, some of which might be able to absorb and store energy by charging batteries, pumping water uphill, compressing Nitrogen, or electrolysing Hydrogen etc. Many generators of different types work in concert to satisfy consumers.

The frequency changes needed to do this seem to be small, about 0.001Hz, so don't worry about electric clocks going mad!

How electricity is sold wholesale and retail is pretty complicated already. DC looks to be another way of allowing the market to cope with peaks and troughs in demand. It's not the only mechanism: real-time tariffs applied by smart meters will encourage consumers to balance the load by increasing prices when capacity is short, and dropping them on bright sunny windy days when renewables are cheap and plentiful.

Dave

Thank you Peter

Roy

Dave,

Hmmm, you had about the same success as me then! Agree I think DC is more about a commercial management solution than a technology one!

I can only relate this to a minute power network on ships with three or four generators to manage where the important factors are frequency (generator prime mover speed), voltage (controlled by AVR) and sychronisation. The "protections" being under and over, frequency and voltage, trips and for the network, preferential trips for load shedding where non essential systems can be knocked off to prevent overload and complete blackout! The overall system frequency depends on the size of transient loads and the speed of reaction, a large motor suddenly cutting in drags frequency down until the generators react and conversely when the motor shuts down the frequency will increase until the generators react. With electronic governor technology the reaction time is a lot faster than the old mechanical governors but there are still fluctuations. Load sharing to prevent motoring is something else. The main problem is programming the cut in / cut out points for surplus / additional generators to provide overlap in capacity due to the run up and synchronisation time of an additional set coming on line! There is significant advantage with a battery providing "instaneous" power to the distribution grid.

With regards to smart meters "controlling" load I have a problem. The constant TV ads telling me a smart meter can save me money are too me misleading! The smart meter itself will have no effect unless I make a conscious decision to switch something off because the smart meter tells me I am costing myself a lot of money! Now granted ££'s is a strong incentive to consumers but to me personally I doubt it would influence me not use the lathe for example! As I see it for a smart meter itself to make a difference in isolation it would need to be linked with inividual appliances programmed to shut down if consumption is excessive. I can tell you if I was halfway through screw cutting a thread and the smart meter indicated excessive consumption / cost and it shut down, I would be heading for so called smart meter with a large hammer! Similarly if I stopped for a tea break and the kettle failed to fire up because the instantaneous price had just increased! Lastly would be extremely unhappy if I decided to go out in my EV and it was depleted by a DC call to back feed the grid! This is all technology that may be beneficial for the planet but makes daily personal decision making and personal choice a lot more complicated. Although those functions can be automated the algorithm controlling is unlikely to pick up a spontaneous whim to do something outside the norm.

At the present time I can use as much power as I like as long as I am prepared to pay, governed only by the size of the incoming supply. I like that. In the future it seems there will be some device or external intervention controlling what I can have, when. I don't like that!

I am also wary of 'smart' technology reliability. Looking at a fleet of vessels old and new, the newer ones incorporating smart systems have lower reliability figures than the old and the cost of rectification almost twice as much.

Paul.

How much would it help if cars all had a solar panel on their roofs?

150-200w/sq metre on a good day, average car roof 3sq metres? - not really promising, might generate 5'ish KWh on a good day.
Of course if they're all stationary on the M25 and linked together they might power a chunk of London...until some job keys them all..

I suppose if one has a car only used occasionally and parked outdoors with enough efficiency to run 200wh/m you'd get a few miles of use but Tesla computers run at 300watts when active with their sentry systems or nav/radios etc.

pgk

Edited By pgk pgk on 08/08/2021 19:53:41

Mark,

Short answer is not much!

Longer answer is in ideal conditions you get around 200w per m2 of panel, depends on the panel, some are more, some less. For a house they reckon the average "sunshine" per day over a year is around 4.5 hrs. Given that static panels are in a fixed orienentation you may on the roof of a car be able to increase that to say 6hrs being optimistic so that would give you 1.2kWh for the day. Given a small EV will have a battery of say around 40kWh and space for around 1m2 of panel that won't take you far!

We looked at it for boats and we have a lot more room than that but also use a lot more power but the cost benefit / benefit is nowhere near close!

Paul.

Related to these discussions: Guy Martin is on Channel 4 at 9pm Monday 9th August (tomorrow as I type).

The programme is called the World’s Fastest Electric Car? Seems that he is converting a VW Beetle to Electric power and going for a record.

Might be worth watching for info on EV systems generally.and he provides good shows.

Edited By V8Eng on 08/08/2021 23:27:30