-50 c/kWh is a lot, I just wish we would have those prices here in Finland.
Meanwhile my electricity bill for June came in:
Consumption: 498,31 kWh
Price: 4,89 c/kWh
Cost: 29,25 € including tax 24%, margin 0,25c/kWh and monthly fee 4,9€
Average spot price in June: 5,37 c/kWh
Savings: 9,04% below spot average
Savings: 50,2% below local energy company fixed price
We currently have diswasher, washing machine and ground source heat pump under spot price optimisation.
This topic was automatically closed 41 days after the last reply. New replies are no longer allowed.
Thanks @mstormi for re-opening this thread upon my request!
Just got my electricity bill for September. here is my savings from electricity use since April this year:
| Spot electricity | April | May | June | July | August | September |
|---|---|---|---|---|---|---|
| consumption [kWh] | 854 | 613,06 | 498,31 | 436,65 | 515,12 | 677,3 |
| basic fee [€/mth] | 4,35 | 4,9 | 4,9 | 4,9 | 4,9 | 4,9 |
| price [c/kWh] | 5,7305 | 3,2804 | 4,6364 | 4,1087 | 8,2108 | 2,5401 |
| margin [c/kWh] | 0,22 | 0,25 | 0,25 | 0,25 | 0,25 | 0,25 |
| Total | 55,17 € | 26,54 € | 29,25 € | 23,93 € | 48,48 € | 23,80 € |
| Average spot price | 6,661 | 3,3 | 5,372 | 4,085 | 8,23 | 4,07 |
| Savings [c/kWh] | 0,9305 | 0,0196 | 0,7356 | -0,0237 | 0,0192 | 1,5299 |
| Savings [%] | 14 % | 1 % | 14 % | -1 % | 0 % | 38 % |
| Savings [€] | 7,9 € | 0,1 € | 3,7 € | -0,1 € | 0,1 € | 10,4 € |
| Local energy company | ||||||
| basic fee [€/mth] | 2,5 | 2,5 | 2,5 | 2,5 | 2,5 | 2,5 |
| price [c/kWh] | 13,18 | 13,18 | 9,82 | 9,82 | 9,82 | 8,79 |
| Total | 115,06 € | 83,30 € | 51,43 € | 45,38 € | 53,08 € | 62,03 € |
| Savings [%] | 52 % | 68 % | 43 % | 47 % | 9 % | 62 % |
| Savings [€] | 59,9 € | 56,8 € | 22,2 € | 21,4 € | 4,6 € | 38,2 € |
Total savings 203,1 € against local energy company prices and 22,1 € against spot average price.
Yeah. I don’t have time to calculate the exact price diffs like above, but here are the stats from this June onwards.
June 2023
July 2023
August 2023
Sep 2023
October 2023 so far
Cheers,
Markus
Very interesting statistics. I have been interested in the Välkky contract, too. Will stay with spot price for now, though.
I will change back to a spot price contract for sure next summer when the remaining fixed period contract ends for us.
Not that there would be anything wrong with these consumption factor agreements (Väre Välkky, Helen Fiksusähkö, Fortum Duo and others). I honestly believe that this is the future because it’s a shared-risk model between the seller and the buyer which raises the awareness of the consumers. And this awareness we will most definitely need as more and more of the energy production is dependent on weather conditions. And what I consider even more important, the awareness is good for the environment and the future of our planet. If you’re a subscriber to Helsingin Sanomat, you can read more about my thoughts at https://www.hs.fi/mielipide/art-2000008978175.html (it’s from last year August).
Having said this, a pure spot price agreement is going to beat these consumption factor agreements by a big margin if you are able to schedule your consumption like we can. With a spot price contract, our October would be only 1,41 c/kWh so far and September would have been 2,27 c/kWh. You just can’t get these kind of price levels with any kind of fixed or semi-fixed agreement.
If we look at what are the prices in the futuurimarkkina (whatever that is in English) for the next 12 months, the weighted average price is currently being traded at 7.62 c/kWh. Weighted average is calculated so that 65% of the annual energy consumption takes place in the heating season and 35% during the summer.
Väre sells 12 month Välkky at 9.70 c/kWh +/- consumption factor at the moment, Helen is at 9.90 c/kWh. So their margin (in the base price) is a bit more than 2.0 c/kWh with these agreement types.
Based on the past experience and the data shown above, our household can be quite confident that we can beat the average spot price by 30%. So for us the next 12 months should be something like 5,33 c/kWh. This would mean that our consumption factor would be around 7.62 - 5.33 = -2.29 c/kWh.
We would need to get -4.0 c/kWh consumption factor to get even with a pure spot price agreement but with the estimation above, we can reach -2.29 c/kWh. So for our household, a pure spot price contract will be cheaper unless the current mess in the World evolves to WW III and the prices go crazy again.
Cheers,
Markus
Energy bill for October just came:
| Spot | April | May | June | July | August | September | October |
|---|---|---|---|---|---|---|---|
| consumption [kWh] | 854 | 613,06 | 498,31 | 436,65 | 515,12 | 677,3 | 1259,5 |
| basic fee [€/mth] | 4,35 | 4,9 | 4,9 | 4,9 | 4,9 | 4,9 | 4,9 |
| price [c/kWh] | 5,7305 | 3,2804 | 4,6364 | 4,1087 | 8,2108 | 2,5401 | 3,0403 |
| margin [c/kWh] | 0,22 | 0,25 | 0,25 | 0,25 | 0,25 | 0,25 | 0,25 |
| Total | 55,17 € | 26,54 € | 29,25 € | 23,93 € | 48,48 € | 23,80 € | 46,34 € |
| Average spot price | 6,661 | 3,3 | 5,372 | 4,085 | 8,23 | 4,07 | 4,66 |
| Savings [c/kWh] | 0,9305 | 0,0196 | 0,7356 | -0,0237 | 0,0192 | 1,5299 | 1,6197 |
| Savings [%] | 14 % | 1 % | 14 % | -1 % | 0 % | 38 % | 35 % |
| Savings [€] | 7,9 € | 0,1 € | 3,7 € | -0,1 € | 0,1 € | 10,4 € | 20,4 € |
| Local energy company | |||||||
| basic fee [€/mth] | 2,5 | 2,5 | 2,5 | 2,5 | 2,5 | 2,5 | 2,5 |
| price [c/kWh] | 13,18 | 13,18 | 9,82 | 9,82 | 9,82 | 8,79 | 8,79 |
| Total | 115,06 € | 83,30 € | 51,43 € | 45,38 € | 53,08 € | 62,03 € | 113,21 € |
| Savings [%] | 52 % | 68 % | 43 % | 47 % | 9 % | 62 % | 59 % |
| Savings [€] | 59,9 € | 56,8 € | 22,2 € | 21,4 € | 4,6 € | 38,2 € | 66,9 € |
35% below spot average price. Total savings against local electric company 270 € since beginning of April when I took the system in use.
Energy bill for November just came, total savings in energy cost this year so far 334,3 €
| Spot | April | May | June | July | August | September | October | November |
|---|---|---|---|---|---|---|---|---|
| consumption [kWh] | 854 | 613,06 | 498,31 | 436,65 | 515,12 | 677,3 | 1259,5 | 1584,64 |
| basic fee [€/mth] | 4,35 | 4,9 | 4,9 | 4,9 | 4,9 | 4,9 | 4,9 | 4,9 |
| price [c/kWh] | 5,7305 | 3,2804 | 4,6364 | 4,1087 | 8,2108 | 2,5401 | 3,0403 | 4,3297 |
| margin [c/kWh] | 0,22 | 0,25 | 0,25 | 0,25 | 0,25 | 0,25 | 0,25 | 0,25 |
| Total | 55,17 € | 26,54 € | 29,25 € | 23,93 € | 48,48 € | 23,80 € | 46,34 € | 77,47 € |
| Average spot price | 6,661 | 3,3 | 5,372 | 4,085 | 8,23 | 4,07 | 4,66 | 5,66 |
| Savings [c/kWh] | 0,9305 | 0,0196 | 0,7356 | -0,0237 | 0,0192 | 1,5299 | 1,6197 | 1,3303 |
| Savings [%] | 14 % | 1 % | 14 % | -1 % | 0 % | 38 % | 35 % | 24 % |
| Savings [€] | 7,9 € | 0,1 € | 3,7 € | -0,1 € | 0,1 € | 10,4 € | 20,4 € | 21,1 € |
| Local energy company | ||||||||
| basic fee [€/mth] | 2,5 | 2,5 | 2,5 | 2,5 | 2,5 | 2,5 | 2,5 | 2,5 |
| price [c/kWh] | 13,18 | 13,18 | 9,82 | 9,82 | 9,82 | 8,79 | 8,79 | 8,79 |
| Total | 115,06 € | 83,30 € | 51,43 € | 45,38 € | 53,08 € | 62,03 € | 113,21 € | 141,79 € |
| Savings [%] | 52 % | 68 % | 43 % | 47 % | 9 % | 62 % | 59 % | 45 % |
| Savings [€] | 59,9 € | 56,8 € | 22,2 € | 21,4 € | 4,6 € | 38,2 € | 66,9 € | 64,3 € |
In our household the ground source heat pump, electric car charging, dishwasher and washing machine are spot price optimized with OpenHAB and the solution developed by @masipila Control a water heater and ground source heat pump based on cheap hours of spot priced electricity - #13 by masipila
For those new to the thread, the table above compares our energy bill to spot average energy price and below that to the local energy company energy price, which currently would be 8,79c/kWh. I use this price as reference for calculating the savings, as we used to buy energy from them before changing to spot price. Markus’ code is quite effective as we have been able to keep energy cost below average spot price for every month except July, when we used the least amount of energy of the whole year. I am honestly quite impressed by the performance of the solution.
Here is our energy usage summary from February to November 2023 when we have been using spot energy and the control system developed by @masipila
Some background information that explains some of the consumption month values might be in order. Totally we heat 250m2 although the garage and basement are at lower temperatures. Besides the ground heating system we have a solar heating system, a solar electricity system with a battery and an electric car. If it gets very cold or the spot price is exceptionally high we can also heat with wood. As we also have a 2 000L heat storage and a 500L hotwater storage that can be heated with the ground heating pump we have modified the original code so that all our heating is done during the cheapest hours between 0.00 and 8.00.
During the time of the year when very little solar energy is available we charge the battery with the cheaper electricity during the night and use it from the battery during the day. The battery can provide the energy for the base consumption of the house and occasional use of the coffee machine and the microwave oven for almost the whole day Food making is often done with the woodfired stove.
The washing machine and dishwasher are both manually timed to the cheapest hours.
More information about our systems can be found in Finnish at http://sirrai.com/html/Sivu03.html
No long term stats, but here’s my month-to-date snapshot for December
It’s interesting as my home has a pretty common ‘average’ hardware setup. No EV.
12kW heat pump with average-sized buffers (300l+200l), solar plant (12kWp), consumption (4 persons).
Both reports are taken from my energy management system (commercial but openHAB based for those that wouldn’t know).
So it’s almost 25% savings compared to a fixed price tariff of 35ct which was the average value in Germany in 2023.
Also note the line doing the math “what-if-I-had-no-PV”. Tomorrow it’s winter solstice and this is showing how little a PV contributes at this time of the year. Post #11 in comparison gives an impression of how it looks like in spring with little heating needed.
Also, I’m in Germany where prices are much higher, particularly because of (fixed) transmission cost, so saving percentages don’t look as great as in Finland.
Impressive figures @ruxu and also @mstormi !
Here are our updated stats since August 2022 which was the first month when I had the automation in place. Currently ongoing month 2023-12 is until Dec 21.
| Month | Consumption, kWh | Market avg, c/kWh | Our avg, c/kWh | Diff, c/kWh | Diff % | Välkky, c/kWh | Ref 1, EUR | Ref 2, EUR | Actual, EUR |
|---|---|---|---|---|---|---|---|---|---|
| 2022-08 | 518 | 32.4 | 22.5 | -9.9 | -30.56% | 4.9 | 204 | 119 | 25 |
| 2022-09 | 625 | 26.6 | 18.6 | -8.0 | -30.08% | 6.8 | 202 | 119 | 43 |
| 2022-10 | 873 | 14.1 | 8.9 | -5.2 | -36.88% | 9.6 | 152 | 81 | 84 |
| 2022-11 | 1034 | 24.2 | 20.2 | -4.0 | -16.53% | 10.8 | 305 | 213 | 112 |
| 2022-12 | 1503 | 27.1 | 24.2 | -2.9 | -10.70% | 11.9 | 496 | 370 | 179 |
| 2023-01 | 1369 | 8.9 | 6.9 | -2.0 | -22.47% | 12.8 | 152 | 100 | 175 |
| 2023-02 | 1570 | 8.82 | 6.0 | -2.8 | -31.75% | 12.0 | 173 | 101 | 188 |
| 2023-03 | 1723 | 8.16 | 5.7 | -2.4 | -30.00% | 12.4 | 177 | 105 | 213 |
| 2023-04 | 975 | 6.66 | 4.7 | -2.0 | -30.03% | 12.8 | 82 | 49 | 125 |
| 2023-05 | 890 | 3.28 | 2.2 | -1.1 | -33.54% | 13.7 | 39 | 23 | 122 |
| 2023-06 | 719 | 4.24 | 3.4 | -0.8 | -20.00% | 14.0 | 40 | 27 | 100 |
| 2023-07 | 596 | 4.08 | 2.9 | -1.2 | -29.41% | 13.6 | 32 | 20 | 81 |
| 2023-08 | 704 | 8.23 | 5.1 | -3.2 | -38.40% | 5.7 | 73 | 39 | 40 |
| 2023-09 | 672 | 4.08 | 2.3 | -1.8 | -44.36% | 7.1 | 36 | 18 | 48 |
| 2023-10 | 1319 | 4.67 | 2.4 | -2.3 | -49.25% | 6.6 | 80 | 37 | 87 |
| 2023-11 | 1642 | 8.63 | 2.8 | -5.8 | -67.21% | 3.1 | 178 | 53 | 51 |
| 2023-12 | 1319 | 11.5 | 10.1 | -1.4 | -12.17% | 7.5 | 188 | 138 | 99 |
| TOTAL | 2608 | 1611 | 1771 |
As mentioned before, we have the “consumption factor” kind of an agreement (Väre Välkky)
A pure spot price agreement would have been 160 € cheaper than Välkky (assuming that we would have the same automation system as we now have). But if we would just have a spot price contract and no automation, we would have been paying 837 € more than what we have now being paying with Välkky so that’s basically the amount of money saved so far with automation.
I can see @ruxu also benefited from a nice Black Friday discount last month when half a day was priced at -0.62 € / kWh thanks to our dear Norwegian neighbors. That one day dumped our monthly consumption factor to -5.8 c/kWh so we paid 3.1 c/kWh for the whole month’s energy. 
Happy holidays to everybody!
Cheers,
Markus
| Spot | April | May | June | July | August | September | October | November | December | Total 2023 | |
|---|---|---|---|---|---|---|---|---|---|---|---|
| consumption [kWh] | 854 | 613,06 | 498,31 | 436,65 | 515,12 | 677,3 | 1259,5 | 1584,64 | 1908,28 | 8346,86 | |
| basic fee [€/mth] | 4,35 | 4,9 | 4,9 | 4,9 | 4,9 | 4,9 | 4,9 | 4,9 | 4,9 | 43,55 € | |
| price [c/kWh] | 5,7305 | 3,2804 | 4,6364 | 4,1087 | 8,2108 | 2,5401 | 3,0403 | 4,3297 | 7,9216 | 4,8665 | |
| margin [c/kWh] | 0,22 | 0,25 | 0,25 | 0,25 | 0,25 | 0,25 | 0,25 | 0,25 | 0,25 | 0,25 | |
| Total | 55,17 € | 26,54 € | 29,25 € | 23,93 € | 48,48 € | 23,80 € | 46,34 € | 77,47 € | 160,84 € | 491,82 € | |
| Average spot price | 6,661 | 3,3 | 5,372 | 4,085 | 8,23 | 4,07 | 4,66 | 5,66 | 9,4591 | 5,7219 | |
| Savings [c/kWh] | 0,9305 | 0,0196 | 0,7356 | -0,0237 | 0,0192 | 1,5299 | 1,6197 | 1,3303 | 1,5375 | 0,8554 | |
| Savings [%] | 14 % | 1 % | 14 % | -1 % | 0 % | 38 % | 35 % | 24 % | 16 % | 15 % | |
| Savings [€] | 7,9 € | 0,1 € | 3,7 € | -0,1 € | 0,1 € | 10,4 € | 20,4 € | 21,1 € | 29,3 € | 92,91 € | |
| Local energy company | |||||||||||
| basic fee [€/mth] | 2,5 | 2,5 | 2,5 | 2,5 | 2,5 | 2,5 | 2,5 | 2,5 | 2,5 | 22,5 | |
| price [c/kWh] | 13,18 | 13,18 | 9,82 | 9,82 | 9,82 | 8,79 | 8,79 | 8,79 | 11,83 | 10,45 € | |
| Total | 115,06 € | 83,30 € | 51,43 € | 45,38 € | 53,08 € | 62,03 € | 113,21 € | 141,79 € | 228,25 € | 893,5 € | |
| Savings [%] | 52 % | 68 % | 43 % | 47 % | 9 % | 62 % | 59 % | 45 % | 30 % | 45 % | |
| Savings [€] | 59,9 € | 56,8 € | 22,2 € | 21,4 € | 4,6 € | 38,2 € | 66,9 € | 64,3 € | 67,4 € | 401,7 € |
We took @masipila 's control system into use in April. System controls heating, EV charging, dishwasher and washer.
This January is going to be quite interesting for us because of the consumption factor agreement and the all-time high spot prices on Jan 5th.
Our contract is 8.8 +/- consumption factor. On Jan 5th the average price of the day was 110 c/kWh, which is about 10x compared to other days. Because we were able to reduce our consumption during the day, our consumption factor on a daily level was -34 c/kWh. Of course this will not be the factor for the whole month but for Jan 1 - Jan 6 period we are at -10.0 meaning that if the month would end now, we would not pay a dime.
I would guestimate that the whole month’s consumption factor will land somewhere on the ballbark of -5 so we would pay 8.8-5=3.8 c/kWh. The January average market price is 33 c/kWh at the moment but it will come down because Jan 5th pulls the average heavily at the moment but in any case the consumption factor agreement is going to beat a pure spot price contract on this particular month quite much (we will pay it back on summer months when the market price is less than 8.8 c/kWh, though).
Money saved!
Here is our savings data for 2-12/2023. The savings with the system was 206€ so the system components are paid in one year. We coped with the 5.1.2024 extreme spot prices by heating all our heat storages with wood in the evening 4.1 to max. temperatures. The electric water heater and the ground heating pump were in standby state. The solar system battery was also charged to 100% during the cheap hours and then recharged at cheapest daytime hour on 5.1 back to 100%. The total additional electricity cost for us during that day was about 12€ compared to a average day.
Our total electricity costs (electricity, transfer costs, monthly basic fees and taxes) for 12 months 2023 was 1 140€, an average of 95€ / month. This also includes about 1 500kWh for charging the EV.
| Spot | Total 2024 | January | |
|---|---|---|---|
| consumption [kWh] | [kWh] | 2008,64 | 2008,64 |
| basic fee | [€/mth] | 4,9 | 4,9 |
| price | [c/kWh] | 11,6895 | |
| margin [c/kWh] | [c/kWh] | 0,25 | |
| Total | 244,72 € | 244,72 € | |
| Average spot price | 13,1782 | 13,1782 | |
| Savings | [c/kWh] | 1,4887 | |
| Savings | [%] | 11 % | |
| Savings | [€] | 29,9 € | |
| Local energy company | |||
| basic fee | [€/mth] | 2,5 | 2,5 |
| price | [c/kWh] | 12,76 | 12,76 |
| Total | [€] | 258,80 | 258,80 € |
| Savings | [%] | 5 % | |
| Savings | [€] | 14,08 |
11% under spot average price in January.
I just published a new version of the optimization solution as an npm package. Full documentation is available at
| Actual consumption | Total 2024 | January | February | March | |
|---|---|---|---|---|---|
| consumption [kWh] | [kWh] | 4881,43 | 2008,64 | 1584,54 | 1288,25 |
| basic fee | [€/mth] | 14,7 | 4,9 | 4,9 | 4,9 |
| price | [c/kWh] | 11,6895 | 6,2043 | 6,2025 | |
| margin [c/kWh] | [c/kWh] | 0,25 | 0,25 | 0,59 | |
| Total | 444,30 € | 244,72 € | 107,17 € | 92,40 € | |
| Average spot price | [c/kWh] | 8,976 | 13,1782 | 6,4 | 7,35 |
| Savings | [c/kWh] | 1,4887 | 0,1957 | 7 | |
| Savings vs spot average | [%] | 11 % | 3 % | 16 % | |
| Savings | [€] | 47,79 | 29,9 € | 3,1 € | 14,8 € |
| Local energy company | |||||
| basic fee | [€/mth] | 7,5 | 2,5 | 2,5 | 2,5 |
| price | [c/kWh] | 12,76 | 8,94 | 8,94 | |
| Total | [€] | 520,63 | 258,80 € | 144,16 € | 117,67 € |
| Savings | [%] | 15 % | 5 % | 26 % | 21 % |
| Savings | [€] | 76,33 | 14,08 | 36,99 | 25,27 |
Edit: Updated 7.4.2024
16% under average spot price in February. Total savings 2024 against Spot 47,79€ and against local fixed price 76,33€.
