Family House Kalvodova in Jeseník
The annual electricity consumption is approximately 12 MWh. Heating is provided by the FENIX electric direct heating system, with the highest electricity consumption during the heating season. Hot water heating is realized by an electric boiler with an integrated heat pump. Additionally, a wood fireplace is used.
In the fall of 2022, a photovoltaic power plant with a capacity of 99 kWp was installed on the south-facing roof and adjacent shelter. The PV system was supplemented with a home battery storage HES with a total battery capacity of 411 kWh.
Since June 2023, the supply and purchase of electricity have been carried out under a spot pricing regime. From this month, detailed monthly statements are available. Within the HES home storage, a control algorithm function has been launched, which creates a plan for the behavior of the photovoltaic system based on the prediction of sunlight, consumption prediction, and spot electricity prices for the next day. It then controls the system to achieve the best economic result.
Example of system behavior on a sunny day – the PV production is accumulated in the batteries throughout the day, and targeted supply to the grid occurs in the evening hours when the spot price of electricity is highest.
In the monitored period 06/2023 – 12/2023, an average price of 0.85 CZK/kWh was achieved, including all fees.
Detailed Monthly Operational Results
| Period | Total Consumption (kWh) |
Grid Draw (kWh) |
PV Production (kWh) |
Supply to Grid (kWh) |
Grid Draw Cost (CZK) |
Grid Supply Income (CZK) |
Energy Costs (CZK) |
Achieved Price (CZK/kWh) |
|---|---|---|---|---|---|---|---|---|
| 06/2023 | 435 | 215 | 1 084 | 864 | 1 560 | 2 219 | -659 | -1,5 |
| 07/2023 | 287 | 252 | 1 144 | 1 109 | 1 345 | 2 425 | - 1 080 | -3,7 |
| 08/2023 | 359 | 348 | 919 | 908 | 1 531 | 2 342 | -811 | -2,2 |
| 09/2023 | 425 | 352 | 1 018 | 945 | 1 515 | 3 121 | -1 606 | -3,7 |
| 10/2023 | 642 | 570 | 581 | 509 | 2 126 | 1 565 | 561 | 0,87 |
| 11/2023 | 1 226 | 1 097 | 280 | 151 | 3 865 | 435 | 3 429 | 2,8 |
| 12/2023 | 1 739 | 1 622 | 230 | 113 | 4 662 | 181 | 4 481 | 2,6 |
| Total | 5 113 | 4 456 | 5 256 | 4 599 | 16 604 | 12 288 | 4 316 | 0,85 |
The monthly results for 2024 so far confirm the very good performance of the system:
| Period | Total Consumption (kWh) |
Grid Draw (kWh) |
PV Production (kWh) |
Supply to Grid (kWh) |
Grid Draw Cost (CZK) |
Grid Supply Income (CZK) |
Energy Costs (CZK) |
Achieved Price (CZK/kWh) |
|---|---|---|---|---|---|---|---|---|
| 01/2024 | 2 111 | 1 816 | 328 | 33 | 8 493 | 47 | 8 446 | 4,0 |
| 02/2024 | 1 157 | 794 | 402 | 39 | 3 638 | 67 | 3 571 | 3,1 |
| 03/2024 | 1 134 | 493 | 763 | 122 | 2 574 | 131 | 2 443 | 2,1 |
| 04/2024 | 706 | 190 | 914 | 398 | 1 303 | 722 | 581 | 0,8 |
| 05/2024 | 498 | 169 | 1 051 | 722 | 1 168 | 1 529 | -361 | -0,7 |
| 06/2024 | 439 | 155 | 1 022 | 738 | 1 297 | 1 955 | -658 | -1,5 |
| 07/2024 | 371 | 155 | 1 092 | 876 | 1 232 | 2 159 | -927 | -2,5 |
| 08/2024 | 386 | 176 | 1 060 | 850 | 1 407 | 2 674 | -1 267 | -3,28 |
| 09/2024 | 485 | 252 | 830 | 597 | 1 630 | 1 742 | -112 | -0,23 |
| 10/2024 | 850 | 408 | 669 | 227 | 2 342 | 770 | 1 572 | 1,85 |
| 11/2024 | 1 782 | 1 398 | 459 | 77 | 8 411 | 634 | 7 777 | 4,36 |
| 12/2024 | ||||||||
| Total | 9 919 | 6 006 | 8 590 | 4 602 | 33 495 | 12 430 | 21 065 | 2,12 |
Prices include VAT.
