Differences between smart meter reading and my own solar reading

dshakey

So recently moved to the smart ev plan with bird gais and now get to see my daily kWh usage from the smart meter. But it's nearly half of what my own energy meter reads

For example. My ev charging at 7kw and see that house pulling around 7.5 to 8kw when this charging. But if I look at same time on smart meter it's only 3.7kw.

Great for me if that is what's happening. Just curious if others seen this.

SD_DRACULA

Well that looks ok to me, it says 3.7kwh used in 30 mins so times two is about 7.5kwh used.

Also it looks like you went past your EV rate and charged until 6:00 😂

KCross

https://www.boards.ie/discussion/2058266945/differences-between-smart-meter-reading-and-my-own-solar-reading

As pointed out above you are confusing instant power (kW) with the total consumed in a time period (kWh).

dshakey

LoL 🤣 how I miss that one .. should had coffee first.

Never going to get the charge in that small window. But double price. Still cheap less than fiver to charge car from 30to 90 percentage

DC999

Adding to that, now you have the night-rate for a few hours start to move other devices to run during that EV window. Looks like it’s about 3 times cheaper than the rest of the night rate. And I’d assume your day rate is higher again.

Dishwasher, washing machine (if not too noisy), tumbler dryer if used….A smart plug should work assuming it holds the setting when it’s powered off. It does on 2 of 3 devices for me. So get one of them and try it. You turn the device on as normal, then turn off in the smart plug app and have it set to turn on again at same time each night.

Plus set immersion to run during that slot if you use it.  

Personally I set the dishwasher to finish just as we get up so it’s heating the kitchen as a ‘rad’. And could get an oil filled radiator in the sitting room to come on before you get up - means the gas heating might not be needed outside the winter months. Horses for course!

dshakey

The solar covers most of my day time power requirements. Well at the mo, see what Winter brings.

Do need to look at adding battery, I send so much to grid that I should store.

Im on the urban ev rate with bord gais. So it's 8c in ev window, 25c at night, 34c day and 47c peak.

bullit_dodger

https://www.boards.ie/discussion/comment/119729678#Comment_119729678

Just on the battery, don't forget that you are getting paid ~€0.15 or thereabouts (don't know what the BG rate is) for units that you export to the grid now. Huge battery fan myself mainly because of Oct->Feb where solar generation isn't great, so you can charge your battery at cheap night rate to use using the day......but it's not a complete given that the financials are favorable now with FIT.

DownByTheGarden

Something wrong there.

According to that screenshot, you have used 0.14 of a kwh in the normal night time hours between midnight and 2am and they are charging you 13c for it. Thats 92c per unit for your night rate.

dshakey

Calc looks right I believe.

140 watts, used over 1 hour at 0.25c is roughly .013.

We know the electric company not going to get this wrong.

https://www.rapidtables.com/calc/electric/energy-cost-calculator.html

dshakey

This was main reason didn't go for battery. Because of FIT but didn't expect rates to way there are. Also didn't appreciate that would need to pull from grid for the extra kw I night need. For example boiling kettle. Having to grid the say get the extra 1kw it needed.

Have solar since may and still haven't been paid for fit. Bord gais I believe is 18.5c per kw

bullit_dodger

https://www.boards.ie/discussion/comment/119729966#Comment_119729966

Ahh, no.

Not 0.25 cent....you wanted 25.0 cent (or 0.25 euro) in your calculator above, and I'd agree with Downbythegarden, something looks wrong there.

dshakey

https://www.boards.ie/discussion/comment/119729995#Comment_119729995

Yes correct. Will need to go again. These figures directly from bord gais. Can't image they be wrong??

browne_rob5

https://www.boards.ie/discussion/comment/119729995#Comment_119729995

The standing charge is included in the Euro amount. 2c per half hour interval.

DC999

https://www.boards.ie/discussion/comment/119729803#Comment_119729803

+1 to that! So if you only pay 8c for that 3 hour window, and get paid ~15c for FIT - then that is 'your battery'. Use as much as you can during the cheapest slot. Every other rate you have is higher than FIT. I'm on the old meter at mo until it's changed. When I do get a smart meter, I'm gonna hammer that 'EV' window.

DownByTheGarden

https://www.boards.ie/discussion/comment/119730013#Comment_119730013

Dont think so. If that is the case then the 1:30 to 2am amount is way off.

I would be querying this because that discrepancy adds up to a huge amount over time.

graememk

https://www.boards.ie/discussion/comment/119730130#Comment_119730130

It's not far off. Within rounding to the nearest cent.

(0.07*0.25) + 2 c = €0.0375

browne_rob5

https://www.boards.ie/discussion/comment/119730130#Comment_119730130

I am on this plan and it is.

1:30 to 2 am looks correct. 2c for electricity (.07 x .25) and 2c for standing charge = 4c

cruizer101

I think it works out, the night rate is 29c per kWh so for 1:30 to 2 thats 29 * 0.07 = 2.03c plus 2c standing charge give 4.03 or 4c

For 0:00 to 0:30 29 * 0.02 = 0.58c plus 2c gives rounded up 3c, similar for 0.03kWh * 29c = 0.87c.

On my own account, when you add up all the cent values throughout the day compared to the total, the total was less for me which accounts for the rounding up to whole cent values, I think.

I might need to download the raw csv and pop it into to excel to fully confirm, I'd be surprised if they are overcharging though.

dshakey

Thanks folks, yes agree doubt they over charging. But of course being difficult.

Here spreadsheet, if interested. I removed my mpnr and serial

https://docs.google.com/spreadsheets/d/1u0vYdVtTphm8fW-ajtslCNKS9qAu0d4O/edit?usp=drivesdk&ouid=110337058844389219191&rtpof=true&sd=true

DC999

https://www.boards.ie/discussion/comment/119730406#Comment_119730406

Cheers, appreciate you sharing as gives me a sense of smart tariffs for when I do get the meter

DownByTheGarden

https://www.boards.ie/discussion/comment/119730406#Comment_119730406

Are there lots of periods in there where you are not getting charged the 2c? That messes with the theory that it 2c per half hour standing charge on the ops screenshot.

cruizer101

The spreadsheet just shows the raw kWh values, the tables and graphs on the website show cost and they include the standing charge averaged out, they are good for giving you a general idea of how your usage is and when you are using electricity but for any decent analysis I think you would want to use the raw csv data. To me I wouldn't average the standing charge out over every half hour I'd rather think of it separately and just analyze the pure usage costs.

dshakey

https://www.boards.ie/discussion/comment/119730668#Comment_119730668

The zero would be when power been taken from the solar. So not pulling from the grid.

graememk

Another thing could be skewing things.

Is the price/kwh after discounts?

Eg a traditional bill it's calculated at the non discount rate and then discount is then taken off?

dshakey

https://www.boards.ie/discussion/comment/119731036#Comment_119731036

Good call. It possible is. Here Sept bill before price increase. I only switched on 12 Sept.

DownByTheGarden

https://www.boards.ie/discussion/comment/119730987#Comment_119730987

Thats what happens with mine. But if the theory about the standing charge being the 2c per half hour was to hold then there should never be any half hour periods with less than 2c per half hour.