Phil Himsworth

A system on a north facing roof will generate iirc 60% of what it would on a south facing roof. It makes more sense to install on a south facing roof if you've got the choice, but even on a north facing roof it would be worthwhile. Maybe back when panels were much less efficient this meant a north facing install was pointless, but it's not now.

Without a battery an east-west split system is arguably better; the peak and total power are lower, but it's spread more evenly throughout the day and is more likely to still be generating into the evening when you are likely to use it most.

With a battery it doesn't really matter as much, as you can use the power whenever you like to some extent. The capacity and charge rate of the battery matters more.

4 hours ago, hayfield said:

part of his plan is to buy cheap electricity (Charging the panels up) at night after discharging his battery during peak hours for best export rates.

There are a few tariffs now where overnight imported electricity is cheaper than exported daytime electricity, so (especially if you have a battery) it makes sense to use as much of the overnight power as you can and export as much of your generation as you can. Octopus Intelligent has 7.5p/kwh overnight import but 16p/kwh daytime export; Eon have a similar rate.  This turns things about a bit; clever EV chargers or solar hot water diverters become unnecessary as it's cheaper to use power overnight and use as little of your own generation as possible, the opposite from a few years ago when maximising your own self consumption was the big thing.

We had a great time yesterday. Some things I can remember;

- Whoever had the idea for the paint-a-racing-car for kids was an absolute genius, my totally-train-agnostic daughter loved it and has been playing with her car since yesterday. There were a few kids outside the hall yesterday zooming them about on the smooth floors, presumably waiting for parents still inside :-)

- Oscar's little N gauge layout was fantastic; it was absolutely stuffed with interesting things. This layout and its little list of things to find probably held our collective attention the longest of all the railway things, probably beaten only by the trucks because of all the huge-trucks-careering-down-the-hill shenanigans.

- The guy scratch building the Star Wars ship has patience I could only aspire to with all the teeny tiny details, I'm sure it'll look epic when it's done.

- The whole concept of actual working model jets still amazes me.

What are the food offerings like? We're wondering what to do for lunch tomorrow...

Yesterday was rubbish, we hardly generated anything. We use a tariff with a good off-peak import rate over winter or a tariff with a good export rate over summer; while switching there is a period of neither, which exactly coincided with yesterday's cold and dark snap in the most expensive way possible. Rats!

An aerial picture of the Telford / Oakengates landslip;

https://www.shropshirestar.com/news/local-hubs/telford/oakengates/2024/03/12/in-pictures-workers-tackle-telford-landslip-thats-caused-travel-chaos-on-shropshires-rail-network/

I don't think it's anything to do with the nearby development, it's a pretty big embankment, that bit isn't particularly near to anything new and it has been extremely wet recently. There have been quite a few trees fall around here recently just because the ground has become so soft it won't hold them up any more.

Mine is a super runner but has developed a bit of a squeak!

There's plenty of grease on the axles, and the drivetrain (from what I can see under the keeper plate), so I don't really know where it's coming from. Before I just start poking oil all over everything that moves does anyone know of any likely culprits?

16 hours ago, big jim said:

wouldn’t fancy the climb from buildwas to lightmoor on the self propelled one though! 

Me neither! Luckily my "stop" is above where it starts getting steep. That said, I think the old line down to Coalport where the Silkin Way is now is even steeper; that's a slog on a bike, I've no idea how trains got up there at all...

Taking a modern train along the SVR must be fun, it must all be very different!

3 hours ago, big jim said:

Track maintenance vehicles 

 

My journey to work runs near the old Ironbridge branch for quite a way; I've often wondered whether something like one of these might make it a bit more interesting 🙂

3 minutes ago, sjp23480 said:

That means their buy back rate is more than the current unit price (~28p per unit). 

Octopus have a few funny tariffs to suit different kinds of systems. Intelligent Go or Intelligent Flux have higher export than import costs at certain times; if you can run from a battery then on Intelligent Go you can import at 7.5p and export at 16p, so it is more lucrative to use night time import and export as much of your own generation as possible.

I don't think I've ever heard anybody say they wish they got a smaller battery. We have a 9.5kwh one but I'm tempted to get more. The PV system earns the money in summer, but the battery probably saves more in winter from running on cheap rate electricity all day at a fraction of the cost.

2 hours ago, big jim said:

Yesterday was cancelled as was todays mainline run

These tests do seem to be cancelled a lot. Do you know if they are booked on a "we might not need to do a run but we'll book everything just in case" or are they runs that should have gone ahead but don't because something has gone wrong somewhere?

I used flexitrack with a join on a bend; in hindsight I wish I had used settrack as the slight kink is the only problematic bit of track on the whole layout.

I did wonder whether a compromise might be to use flexitrack, but instead of joining one length of flexi to another, have a very short cut down length of settrack in between; you could still use flexi to get the curve you want, but the little bit of settrack would hold the rails in the right place at the join. Would this work?

Some gratuitous rail bending with pliers seems to have sorted mine out, but I have wondered about retrofitting the above as a backup option,,,

Mine is an absolutely superb slow runner. It starts slowly and smoothly; even on DC it really oozes the feeling that it's working really hard to get a train moving, I love it.

(It doesn't like going downhill much for some reason mind, I guess it's got a worm drive maybe?, but I can live with that)

12 hours ago, Arun Sharma said:

It seems there is a Press Association statement today saying that the Dept. of Transport wants to get 75% more freight onto the railway.

The target was 95% until something happened recently. A 75% increase by 2050 - over 26 years away - is a very low bar to clear.

12 hours ago, big jim said:

as for the show, what can I say, WOW! what an amazing experience from start to finish

That's great to hear, we're going to see it next year :-)

A recording of the Broadway version is on Disney Plus if you have it and want to relive it again. I've watched and listened to it many times so I'm very excited about it...

7 hours ago, big jim said:

More chaos due to the failed mail train

Do you know what is going on over there? According to Traksy the line is still out of use, even though it's been days! Is it the train or the track?

My layout has a bit of road and a field at the front of the board that is almost like a sacrificial area that can be tampered with; there are a couple of cars, farm animals and odds and ends that the daughter likes fiddling with. This seems to satisfy so the rest of the layout seems safe...

7 hours ago, D7063 said:

Allen Bradley was a make of programmable logic controllers that a few on this forum may be familiar with :)

Still is, I was swearing in frustration at one only today 🙂

1 hour ago, railcar1 said:

Anyone tried running it down a gradient?

I have; it didn't go very well, it seemed to go through a cycle of running away a bit, slowing itself down, then repeating this to the bottom.

That said, that one was one with a bit of a wobble and I think not perfect quartering or something so I'm not sure much should be read into it. I'll try again when it returns.

11 hours ago, hayfield said:

(energy costs are still predicted to fall)

One thing to remember is that while energy is cheaper this year, we aren't getting the monthly £66 (or whatever it was) we were given last winter. I haven't worked out whether the reduced unit cost is wiped out by not getting that...

59 minutes ago, Tony Teague said:

I didn't make a huge amount of progress because there is so much to do that I needed to work out where to start.........which I did and then ran some trains which is always theraputic.

I have a little box of "bushes"; if I have a day when I feel like I should have done something but haven't I have a quick blast of spray glue and stick a few bushes down. It can take seconds, so can even be done last thing at night if need be. It's not a lot, but slowly builds up to something worthwhile, and is better than fretting about having done nothing at all!

46 minutes ago, Nick C said:

I don't agree with these - not down to being a NIMBY, but simply because it's not the most appropriate use of the land. Fields should be used for growing crops or grazing animals, solar panels should be on the roofs of buildings - especially industrial ones.

Land use is not so simple. Far more land is used for growing biofuels than solar panels; this is far less efficient in terms of energy per area than solar, but because it just looks like any other field doesn't get the stick that PV does. Solar panels currently cover less land than airports and far less than golf courses which don't produce anything at all if we're just reducing land to how productive it is.

Solar also doesn't necessarily stop land being used for agriculture; "agrivoltaics" is combining PV and agriculture for mutual benefit, such as providing shading or increasing biodiversity which can boost productivity of surrounding land.

PV is often more profitable than other kinds of land use, so providing farms with additional income that may boost productivity on other land or make sure they can keep going at all.

Solar PV on roofs of commercial buildings and especially new builds is great, but some structures are not suitable and it is inevitably more expensive than just plonking panels on the ground, so it does have a lower cost effectiveness.

2 hours ago, Hobby said:

OK, who the heck are the DNO and what do I have to do if I need to contact them? (My new system is 3.32kW).

Put your postcode into this website and it will tell you:

https://www.energynetworks.org/customers/find-my-network-operator

I've got some signals like this, it's a bit of a nuisance. Theoretically you can just wire the common to 5v and the signal wires to the output channels so setting them to 0 turns them off, but often output lines are able to source current but not sink it so this won't work. I'm not sure what the Arduino does in this respect.

I'm driving mine through a PCA9685 servo / led driver board, and that has an "invert" mode that switches it between conventional (load is between driven output and 0v) and inverted (load is between driven output and 5v). My controller sets that mode on startup and then it all works fine after that.

The advantage of using a servo controller board is that you have a lot more outputs, especially as they can be daisy chained, and the brightness is fully controllable as well.

Your can export up to 16A, or 3.68kw, without having to ask the local Distribution Network Operator (DNO); you just have to tell them after it's installed.

Above that and you have to ask first, and they will tell you how big a system you can have. It will depend on the local network; if you're in an urban area with decent infrastructure it will probably be quite high, if you're out in the sticks with ancient transformers up poles it may be lower. I have a vague recollection that the absolute limit on a single phase supply is 12kw, I think.

Once its all agreed with the DNO, the company you use for exporting power won't care how big your system is. They will want to see the letter from the DNO to check your system is legit, but once they've checked that they will pay you for every unit you export.

If you haven't declared it to the DNO, or installed a system above the maximum size they set, you won't be able to get an export contract and the DNO can probably do various legal things to make you disconnect it. If they find out. I'm not sure how they would find out, but I assume they can measure things at their end and get a good idea if there's more power moving about when it's sunny than there should be.

I assume that the problem doesn't come up much, as if you've got a large system it's in your interest to do it properly so you get paid for your potentially lucrative exports.

3 hours ago, hayfield said:

I still cannot balance the cost of batteries being worth the investment, an electric car might be a better use of our savings as we do few miles and the car is at home during the day 

We got our PV and battery at once so it's very difficult to separate the benefit from both. The PV generates the power but the battery allows us to use much more of it, either overnight or on dull days when we can still run large loads like the washer from a smaller amount of PV without importing. The battery is also a lot more useful over winter when the PV does very little but the battery means we can largely run on much cheaper off-peak electricity. At last winter's prices that's £1.85 of savings each day if we fully discharge the battery, which we did on a lot of days.

Would the system pay for itself faster if we didn't have the battery? I've no idea. I could probably come up with some plausible looking maths that would justify the cost of the battery, but whether it would be based mainly on reality or optimism I don't know.

Mainly though I love being self sufficient with zero carbon power for a lot of the year, and able to run on low carbon power for a lot of the rest.

The entertainment value of it all must have some value; I love looking at all the data it generates about what it's doing. It's a good job phone screens don't suffer from burn-in like old CRTs or the dashboard of the monitoring app would be visible even when the phone is off :-)