navitron
 
Renewable Energy and Sustainability Forum
Welcome, Guest. Please login or register.

Login with username, password and session length
News: Anyone wishing to register as a new member on the forum is strongly recommended to use a "proper" email address - following recent spam/hack attempts on the forum, all security is set to "high", and "disposable" email addresses like Gmail, Yahoo and Hotmail tend to be viewed with suspicion, and the application rejected if there is any doubt whatsoever
 
Recent Articles: Navitron Partners With Solax to Help Create A More Sustainable Future | Navitron Calls for Increased Carbon Footprint Reduction In Light of Earth Overshoot Day | A plea from The David School - Issue 18
   Home   Help Search Login Register  
Pages: [1] 2   Go Down
  Print  
Author Topic: New solar install  (Read 2735 times)
pantsmachine
Jr. Member
**
Offline Offline

Posts: 68


« on: July 21, 2018, 01:37:14 AM »

Morning all,

We had a solar pv array installed last month and are very happy with it. My wife is In Singapore at the moment and i am offshore so it seemed a good time to log grid consumption in an empty house, our son was there one night hence a blip on the 17th to 18th. Anyway, I had a nagging doubt as to the ongoing consumption of power from the grid as displayed in power usage graph on suppliers website and have been tracking it, there is a disparity.

To cut to the chase- In the past 8 days the smart meter for electric has registered a power draw from the grid of 34kwhrs as i would expect since the batteries are not yet installed to feed the fridges/freezers, sky boxes etc during the hours of darkness.

The Sainsbury's online account power usage graph for the same period shows 65.85 kwhrs used.


I would maybe accept that this 65.85 kwhr somehow includes the daily standing charge as part of power usage graph?

But,

34kwhrs @ 13.56p ea = 4.61

65.85kwhr @ 13.56p ea = 8.92

The difference is 4.31, A standing charge of 26p per day for 8 days is 2.08 so there is a disparity even taking into account the standing charge. Do any of you guys have a thought on this?

It looks to me as if Sainsbury's are charging me almost double our usage if they base their bills on the power usage graph even though the same account shows the true usage sent in from our smart meter every day. Am I late here or something, Is this already known about?

They are getting binned next month for Bulb but i am now wondering if we have been getting pumped since we took the contract a couple of years ago?  fume

The gas use is hilarious!  hysteria

Energy usage graph from Sainsbury portal
 01/07 to 12/07 131.26 kwh Elec used
01/07 to 12/07 222.3 kwh Gas used
01/07 to 18/07 179.26 kwh Elec used
01/07 to 18/07 332.3 kwh Gas used
01/07 to 20/07 197.11 kwh Elec used
01/07 to 20/07 374.3 kwh Gas used

Smart meter readings from same account & portal.
10/07/2018 Gas reading 2349
11/07/2018 Elec reading 3548
11/07/2018 Gas reading 2350
12/07/2018 Elec reading 3555
12/07/2018 Gas reading 2350
13/07/2018 Elec reading 3559
13/07/2018 Gas reading 2350
14/07/2018 Elec reading 3563
14/07/2018 Gas reading 2350
15/07/2018 Elec reading 3567
15/07/2018 Gas reading 2350
16/07/2018 Elec reading 3572
16/07/2018 Gas reading 2350
17/07/2018 Elec reading 3576
17/07/2018 Gas reading 2350
18/07/2018 Elec reading 3583
18/07/2018 Gas reading 2350
19/07/2018 Elec reading 3586
19/07/2018 Gas reading 2350
20/07/2018 Elec reading 3589
« Last Edit: July 21, 2018, 02:41:47 AM by pantsmachine » Logged

HUGE insulation depth.
5.12 kw PV system with Solar edge.
4.8 kw Pylon tech battery storage.
All low energy bulbs.
Solar I boost charging 200 ltr OSO system tank.
Balanced CH wet system & Hive 2
Wood fired thermosiphon cedar hot tub.
Masanobu Fukuoka inspired veg garden & fruit trees.
brackwell
Hero Member
*****
Offline Offline

Posts: 2774


« Reply #1 on: July 21, 2018, 06:56:39 AM »

The smart readings, on which payment is billed, will be correct and indicate a background draw of 177W/hr after PV contribution. Which could be say 350W/hr for 50% of the day where the PV is providing the other 50%

I suspect the other is just a typical house usage of your type/history and is just theoretical/indicative which perhaps would be about right if the house was occupied.

If you are on theoretical direct debit payment rather than actual readings then you just need to ring and tell them to change direct debit as you are now producing PV.

I never used to give the background draw much respect but have changed my view on that as 350W/hr x 24 hrs x 365 days = 3,066 kWhr/yr !!   I would suggest this fig is high and worthy of some investigation.
Logged
pantsmachine
Jr. Member
**
Offline Offline

Posts: 68


« Reply #2 on: July 21, 2018, 07:44:51 AM »

Digging further I find that the last 'true' reading on the electric meter reading section of the supplier portal is from the 29th May, the solar went live on the 8th June. The reading on the 29th May was 3247-3589 reading from midnight last night=342 kwhr bought 29th May to 20th July 342/52days= 6.56kwhr bought per day which is fair enough as i was grid connected only from 29th May to 7th June and so the average will be skewed upward.

The sooner we have batteries installed the better as we have produced 980kwhrs since switching on and would prefer that juice to be in a battery bank rather than the grid. I am also surprised that regardless of payment method the usage graph is not accurate. Especially as the data is going to them each day.

I am looking forward to switching to a greener supplier (Bulb). It will be a new chapter.

This is all a learning curve for us and makes for interesting new ways to think and most certainly more power aware. Thanks for your input.

« Last Edit: July 21, 2018, 07:47:42 AM by pantsmachine » Logged

HUGE insulation depth.
5.12 kw PV system with Solar edge.
4.8 kw Pylon tech battery storage.
All low energy bulbs.
Solar I boost charging 200 ltr OSO system tank.
Balanced CH wet system & Hive 2
Wood fired thermosiphon cedar hot tub.
Masanobu Fukuoka inspired veg garden & fruit trees.
nowty
Hero Member
*****
Offline Offline

Posts: 595



« Reply #3 on: July 21, 2018, 11:08:39 AM »

If your getting batteries you may want to consider changing your energy supplier to EBICO with a zero standing charge. As your import goes towards zero, the standing charge really makes a difference.

I am actually with Scottish Power at the moment but again with zero standing charge but the tariff its only available to people who are already with Scottish Power.

My daily import is circa 0.1 kWh at the moment, it used to be 15 kWhs during the summer before all this renewable madness. wackoold

Logged

10kW of PV installed and 45+ MWh generated.
Usable battery storage of 50+ kWh.
Heat storage of 25+ kWh.
6kW Ground Source Heatpump.
200,000+ litres of water harvested from underground river.
A few cold frames and raised beds.
pantsmachine
Jr. Member
**
Offline Offline

Posts: 68


« Reply #4 on: July 21, 2018, 10:35:56 PM »

Thanks Nowty, I appreciate that. Never heard of Ebico but now that I have looked I see them as a good fit for the electricity. Gas on the other hand will likely move to Bulb as we'll still be burning about 22,000 kwh per annum. It makes sense to split them and forget about smart meter loss of data until 2.0 rolls out. That's some system(s) you've got there. I feel like a toddler! Smiley

Best guess I can make is a reduction of 85% on imported sparks and 25% on gas. These reductions are well within the realms of possible. I am enjoying the whole 'unknown' aspect of this until year 1 is in. Keeps me on my toes!

Edit- A combination of Ebico & Zog seems to offer a decent fit for our predicted power needs. Thanks again.
« Last Edit: July 22, 2018, 01:40:47 AM by pantsmachine » Logged

HUGE insulation depth.
5.12 kw PV system with Solar edge.
4.8 kw Pylon tech battery storage.
All low energy bulbs.
Solar I boost charging 200 ltr OSO system tank.
Balanced CH wet system & Hive 2
Wood fired thermosiphon cedar hot tub.
Masanobu Fukuoka inspired veg garden & fruit trees.
Tinbum
Hero Member
*****
Offline Offline

Posts: 1068


« Reply #5 on: July 22, 2018, 09:46:27 AM »

I'm with GB energy for my electric which also has a zero standing charge on their standard variable tariff.
Logged

85no 58mm solar thermal tubes, 28.5Kw PV, 3 x Sunny Backup 5048, 3x Sunny Island 5048, 2795 Ah (135kWh) (c20) Rolls batteries 48v, Atmos wood gasification boiler, Brosley wood burner, 2000lt buffer tank and 250lt DHW
chasfromnorfolk
Hero Member
*****
Offline Offline

Posts: 618


« Reply #6 on: July 22, 2018, 09:58:28 AM »

I'm with GB energy for my electric which also has a zero standing charge on their standard variable tariff.

Must be regional... just had a look at tariffs for East Anglia:  no zeros there!

Chas, with two meters, two standing charges...
Logged
Tinbum
Hero Member
*****
Offline Offline

Posts: 1068


« Reply #7 on: July 22, 2018, 10:14:06 AM »

OOps sorry my mistake- Extra energy-( used to be with GB)
Logged

85no 58mm solar thermal tubes, 28.5Kw PV, 3 x Sunny Backup 5048, 3x Sunny Island 5048, 2795 Ah (135kWh) (c20) Rolls batteries 48v, Atmos wood gasification boiler, Brosley wood burner, 2000lt buffer tank and 250lt DHW
nowty
Hero Member
*****
Offline Offline

Posts: 595



« Reply #8 on: July 22, 2018, 11:32:15 AM »

Gas on the other hand will likely move to Bulb as we'll still be burning about 22,000 kwh per annum.

Snap, unfortunately I have a lot of work to do on my gas addiction. facepalm

I feel some crazy subterranean water sourced heat pump shenanigans coming on. sh*tfan

Logged

10kW of PV installed and 45+ MWh generated.
Usable battery storage of 50+ kWh.
Heat storage of 25+ kWh.
6kW Ground Source Heatpump.
200,000+ litres of water harvested from underground river.
A few cold frames and raised beds.
pantsmachine
Jr. Member
**
Offline Offline

Posts: 68


« Reply #9 on: July 23, 2018, 02:44:38 AM »

It has been an ongoing series of improvements for years which then throw off further ideas. We went from an annual gas consumption of 34,000kwh end of May 16 to 24,000kwh end of May 18. Same house but just got into the nitty gritty of sealing and insulating and balancing the wet system so it was running efficiently. I hope that 24,000kwh drops to less than 18,000kwh across this year as works have been ongoing this Spring/Summer other than the solar install. I am interested to see how much of the gas drop which can be laid at the door of the solar I boost but will never know for sure due to the other works from this year. Claims are for 25% reduction in gas with the Iboost but that seems high? Anyone have one in place for a while?

I'd be interested to read on your heat pump idea? I do like ideas that go against the status quo.
Oh aye, and work!

My wife flies back from Singapore tonight and has bought some sari fabric which we are going to use in the build of a sliding wall mounted screen to split a walkthru between the two distinct halves of the house. Her idea and I think its a cracker and will make a further difference. I hope she has went for mental loud fabric colour and patterns as nothing else will do! Smiley
« Last Edit: July 23, 2018, 06:13:02 AM by pantsmachine » Logged

HUGE insulation depth.
5.12 kw PV system with Solar edge.
4.8 kw Pylon tech battery storage.
All low energy bulbs.
Solar I boost charging 200 ltr OSO system tank.
Balanced CH wet system & Hive 2
Wood fired thermosiphon cedar hot tub.
Masanobu Fukuoka inspired veg garden & fruit trees.
pantsmachine
Jr. Member
**
Offline Offline

Posts: 68


« Reply #10 on: October 01, 2018, 05:30:03 PM »

Sadly no photos, I have been keeping an eye on the power graphs generated by the Goodwe charge controller and noticed a draw in the dark hours of between 200 and spiking to 450 watts on a regular 30 minute basis. This was going on through day time as well but hidden within the general power chatter of daylight. At a rough estimate I would say 2.5kwhrs being wasted. The waste was caused by two of fridge and two of freezer units. Old age, poor seals maybe even low gas had them kicking in and out all the time. Three out of four are now in the skip with two of wonderful silent A+ replacements NOT kicking in and out. In these marginal solar Autumnal days I can see the benefit reflected on the SOC on the batteries and longevity of said C during darkness. Moral of this story? See what load your refrigeration is drawing and address it if need be. Its 24/7 365 and mounts up hellishly. Cheers! Smiley
Logged

HUGE insulation depth.
5.12 kw PV system with Solar edge.
4.8 kw Pylon tech battery storage.
All low energy bulbs.
Solar I boost charging 200 ltr OSO system tank.
Balanced CH wet system & Hive 2
Wood fired thermosiphon cedar hot tub.
Masanobu Fukuoka inspired veg garden & fruit trees.
pantsmachine
Jr. Member
**
Offline Offline

Posts: 68


« Reply #11 on: October 26, 2018, 05:10:59 PM »

On return to home i used a plug in meter to monitor the 2 fridges and 2 freezers over a few days. Three out of four were indeed kicking in far too often. This was down to general age and door seals. Shiny,efficient and as a bonus quiet replacements bought for a few hundred quid. I also ran in a single isolation switch to power off the supply to the 65" TV and the Yamaha soundbar at the same time which were impossible to access easily on a nightly basis.

These works have made a change in background load of
200 watts average spiking to 450 watts to
  90 watts average spiking to 170 watts in the hours of darkness when house is ticking over. The graph has also flattened with times of zero load as well.

I am amazed at the way the solar install has changed the way i view power consumption. I also T'd the dishwasher inlet from cold to hot supply and will be running a hot water feed to the washing machine next time i am home. There is a small margin of obsession in this which i am happy to admit to. The game now is not financial, by this i mean i am not trying to save money. I am now trying to make the house run as efficiently as possible with no change to QOL. I like this game. Smiley
« Last Edit: October 26, 2018, 05:18:57 PM by pantsmachine » Logged

HUGE insulation depth.
5.12 kw PV system with Solar edge.
4.8 kw Pylon tech battery storage.
All low energy bulbs.
Solar I boost charging 200 ltr OSO system tank.
Balanced CH wet system & Hive 2
Wood fired thermosiphon cedar hot tub.
Masanobu Fukuoka inspired veg garden & fruit trees.
andrewellis
Newbie
*
Offline Offline

Posts: 30


« Reply #12 on: October 26, 2018, 06:02:00 PM »

Just be careful taking the hot water supply into the dish washer.  I have just done it and the hot tank is only about 4 meters (2 of 22mm and 2 of 15mm) of pipe from the tank to the dishwasher.  That's about 1 liter.  You would be surprised at how much water sits in the pipes with any decent length of pipe run. You then end up heating a big slug of cold water and then lose the heat from the slug of hot water that replaced it.  The modern dishwashers are also quite frugal with water so aren't taking all the water at once giving a cool down period for hot water in the pipe.  I was thinking I would save quite a bit but it still used quite a bit of energy according to my meter.  15 litres per cycle is only about 600W to heat up to 50degrees.  Most of the energy seems to be running the pumps.

Also for anyone thinking of doing it.  Make sure you check your dishwasher can take a hot input.  Not all can and it will mess with the programs.  They shorten the length of wash time as the water is already hot. 
Logged

4.8kw Solar PV JA Panels, SolarEdge inverter inbound
Nibe F1255 12kw GSHP -> Radiators
Nissan Leaf
oliver90owner
Hero Member
*****
Offline Offline

Posts: 1780


« Reply #13 on: October 26, 2018, 06:59:46 PM »

And possibly a water softener, if included.
Logged
pantsmachine
Jr. Member
**
Offline Offline

Posts: 68


« Reply #14 on: October 26, 2018, 07:12:10 PM »

Hi Andrew,
Thanks for that, all valid points. They also stand for the washing machine as well. We have the kids returning home at the weekends with huge bags of washing so the machine is on all the time! Not too much time for the water to cool down in the pipes before its into the machine for the next load!

Back in the day(3 years ago) we were average 16.4kwh per day on electric (6,000kwh p.a). We are now sub 6kwh per day at the moment with occasional flashes of 2kwh dropping to sub 1kwh  but that has to be a good solar day at this time of year and a quietish house (so not the weekends then) and tbh not often!

I enjoy the variance of it all. I hope to be around 1,600kwh pa in the not too distant future.
« Last Edit: October 26, 2018, 07:14:10 PM by pantsmachine » Logged

HUGE insulation depth.
5.12 kw PV system with Solar edge.
4.8 kw Pylon tech battery storage.
All low energy bulbs.
Solar I boost charging 200 ltr OSO system tank.
Balanced CH wet system & Hive 2
Wood fired thermosiphon cedar hot tub.
Masanobu Fukuoka inspired veg garden & fruit trees.
Pages: [1] 2   Go Up
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.20 | SMF © 2013, Simple Machines
SMFAds for Free Forums
Simple Audio Video Embedder
Valid XHTML 1.0! Valid CSS!