On my E7 tariff it added up the different rates fine, showing cheap usage for filling the various batteries then adding full price units through the day if used. But I agree - I am (was?) lucky - many in house displays aren't worth the transistors they are made from.
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Solar Panels UK - is it worth it?
- Thread starter jdwuk
- Start date
bah used 29kwh grid electric last month vs 13kwh in June. although estimated thats £12 vs £11 last month so I assume the mix of peak/off peak was different.
I’ve hopefully now moved my octopus billing to the 1st (was mid-month) which makes it neater for comparing dashboards/reports with bills. Also means this first one will be a 2-week read but my DD will still go out today and finally clear my debit from last year - £100 debit still, £200 payment (ouch) and hopefully £25 electric, £12 gas will get me positive.
Now I’m curious if I can drop the direct debit a bit or stick it out until we get through a winter first and then using autumn to estimate spring electric should be able to get a reasonable read on a stable DD amount
I’ve hopefully now moved my octopus billing to the 1st (was mid-month) which makes it neater for comparing dashboards/reports with bills. Also means this first one will be a 2-week read but my DD will still go out today and finally clear my debit from last year - £100 debit still, £200 payment (ouch) and hopefully £25 electric, £12 gas will get me positive.
Now I’m curious if I can drop the direct debit a bit or stick it out until we get through a winter first and then using autumn to estimate spring electric should be able to get a reasonable read on a stable DD amount
scdoubleu
Member
Ain't that the truth. Ours failed completely two weeks after the smart meter was installed. So I made my own...
Custom board with an ARM Cortex-M7 SoC, plus 7" touchscreen display. Connects via WiFi to an MQTT broker and InfluxDB server, both of which are populated from the Powerwall's local API.
One of these days I might open-source it.
it *might be* that due to IO being dynamic rate (so - different from E7), so it shows the "average" rate
I have referal if you interested - you will save few quid
Try to contact Otovo - they are very competitive
I have referal if you interested - you will save few quid
WannabeOwner
Well-Known Member
Although, if car is at home during the day, and does a reasonable mileage (bit of an oxymoron, unless you work nights! or have two cars - one-in-the-wash, so to speak) then spilling excess PV to car, instead of using Off Peak (for around 8 months of the year) can help the maths.
The shading bothers me, because that can have a big impact. Cut the trees down? (I suppose if that is "demolish the house next door" that's a bit more tricky!)
Orientation would bother me less. East West (IMO) is far better than South. Twice the roof area to put panels on, and East starts up in the morning maybe an hour before South, and West finishes an hour later - both at times when you are more likely to be at home, and can use the generated power. Whereas if you are out-to-work then the bigger spike, on South, at midday might just wind up as Export. If you have a battery you can shove the South-spike into that, but East /West still preferable IMO. In the morning battery may be border-line for empty, and the earlier sun from East will power the house and in the evening the West will keep the house running later, meaning battery takes over later, and has fewer overnight-hours to support the house (than South-only)
Two roof panels is 2x the number of PV panels, of course, but nothing like 2x the total cost.
Even doing North is worthwhile (provided that the North roof is not too steeply sloping). In Summer North will give you around 75% of South, but because, in mid Summer, the sun rises a long way North-of-East, and sets North-of-West, the North PV gets the benefit of Early / Late generation (similar to East & West orientated roof) and lengthen the "solar generating day"
If you've not already found it have a go with PVWatts - do a simulation for each roof area / orientation / slope. I recommend looking at the generation for each month (rather than just "annual")
I was investigating the difficult to use roof problem for my parents, so generated this pretty picture:
This is for really quite far north in Scotland btw, angles of where it starts mattering would change as you head south. As you can see, North east facing on a 25 degree roof is actually still quite productive. In my parent's case they have a multitue of weird shapes, veluxes and so on on the SW roof, but the NE roof is almost completely free of obstructions and sticking 7-10kw on there looks pretty viable.
Other option would be some ground mounted ones somewhere on the field that surrounds the house, but that might run into planning problems that you get a pass on when fitting to the house.
I gave up on expecting accurate DD estimates from energy companies ... and then it was pointed out to me that you can simply ask your supplier to use a Variable DD and then you pay your actual bill amount each month automatically. Brilliant, problem solved ... no build up of money sitting in energy company account and also no build up of debt. Highly recommended!
Drew57
Active ember
Yes, I used to be on variable DD with my previous supplier and the same with Octopus since joining four years ago.
With Solar & batteries, usage varies so wildly through the seasons it suits us to just pay what we have consumed each month (June-July was £3.28 plus the standing charge, May-June even less because we were overseas for much of it).
With Solar & batteries, usage varies so wildly through the seasons it suits us to just pay what we have consumed each month (June-July was £3.28 plus the standing charge, May-June even less because we were overseas for much of it).
Not true the battery usage moving from of peak to daytime can be worth something like 10p per kwh to the grid. Also electricity companies don't pay any network charges for power you export between 3pm-7pm.
Pete UK
Member
Nah, it was correct from the smart meter and IHD. I paid about £800+ for electricity in December and Jan ~ when I was with OVO !
Unfortunately.
Hence investigating and installing solar + batteries ASAP !
This is cheating as its only 2 weeks worth - moving my billing date from mid-month to end of month. So the electric is quite high. But importantly for me, that'll be +£80 when my DD goes out tomorrow. Thats a relief after being £500 in debit around this time last year (although technically correct, octpus just didn't read my meter for 6 months and I carried on paying way too little at £80 a month at the time)
As for variable DD - i'd prefer a stable amount and then do corrections at the end of the year. We do that across as much as possible to have stable outgoings. But I'll do the math myself and not rely on the energy company. Then any corrections are on me.
even yearly expenses like insurance, amazon prime etc we work out as a monthly amount and put that in a 'yearly' pot to avoid too many surprises. We also have some buffer in there which is our 'white goods' rainy day so we can afford to replace eg a fridge/dishwasher each year if it goes kaput - then sweep into savings if we dont use it. Although I'm trying to use that to update our kit - like moving to induction hob even though technically the gas isn't broken.
Technically the gas -is- broken. This is the great realisation.
Also, induction is amazing. Cooks as well as gas, as easy as the counter top to keep clean. 3 years later mine still looks like new, no need for fancy cleaning rituals like older electric ceramic hobs.
