Sealminer A4 Ultra Hydro
Bitcoin & Bitcoin Cash ASIC Miner
886TH
HASHRATE
9.45W/TH
EFFICIENCY
8373W
POWER
£862.14
EST. MONTHLY
NO PAYBACK
EST. ROI
Image: RIVA GmbH Engineering, via Backnanger Kreiszeitung · Original source.
Renewables and heat reuse
In November 2024, Deutsche Telekom announced a pilot with Bankhaus Metzler at RIVA Engineering in Backnang. Metis Solutions hosts the container and Telekom MMS operates the miners. RIVA has on site photovoltaic generation. The purpose is to collect field evidence for flexible use of surplus electricity.
- Project at a glance
- Industrial solar-surplus pilot
- Source date and context
- 4 November 2024
- Published financial detail
- The sources reviewed do not include full project accounts.
- Our comparison
- A UK example per 1,000 miner kWh
About 5 minutes to read
A pilot designed to gather operating evidence
Deutsche Telekom announced the RIVA pilot with Bankhaus Metzler in November 2024. Metis Solutions hosts the container at RIVA Engineering in Backnang, and Telekom MMS operates the miners. RIVA has its own photovoltaic generation. The stated purpose is to gather field data about a flexible mining load using surplus electricity, rather than to publish a finished investment return.
“Surplus energy is converted into digital values through the miners.”
Using surplus solar power at an engineering business
Industrial rooftop PV→measured surplus→controllable Bitcoin container
The key comparison is what would happen with the miners switched off. The electricity might be exported, stored, used elsewhere at the factory or curtailed. Recording that alternative alongside the mining load makes the trial useful. Grid service payments need their own contract and eligibility checks; flexibility alone does not establish an income stream.
What the numbers could look like in the UK
The calculation below uses assumed UK prices to show how the costs fit together. It is our example, not this project’s reported earnings. Replace the inputs with current machine estimates and the costs at your own site.
Illustrative UK calculation
Income and running costs
1,000 kWh used by miners, plus 50 kWh for pumps and fans. All amounts in pounds.
Operating contributionBefore equipment and installation costs
£15.901.59p per miner kWh
Here, using the electricity for mining gives up a 5p/kWh export payment. That cost includes the 50 kWh used by pumps and fans. It is the value of an alternative sale, so it is not also charged as a grid electricity bill. The example assumes the generation equipment already exists.
| Mining income | 8p per miner kWh; an assumed rate, not a live earnings estimate |
|---|---|
| Electricity | 5p/kWh × 1,050 kWh = £52.50 |
| Pool fee | 2% of gross mining income |
| Useful heat | 0% of miner electricity = 0 kWh; no heat income assumed |
| Other running costs | £10 per 1,000 miner kWh; an allowance to replace with your own costs |
| Costs still to add | Equipment, installation, finance, tax, depreciation, major replacements and any costs above the allowance |
The contribution is what remains from mining income and useful heat after the stated running costs. It is not net profit: the equipment and other excluded costs still have to be recovered. Pumps and fans use electricity but earn no mining income in this calculation.
| Gross income per miner kWh | Operating contribution |
|---|---|
| 5p | −£13.50 |
| 8p Chart example | £15.90 |
| 11p | £45.30 |
- Mining income needed to cover running costs
- 6.38pper miner kWh
- Highest electricity cost or export value supported
- 6.51pper total electricity kWh
These are two ways to read the same example. Adding equipment costs or a larger maintenance allowance raises the income needed and reduces the electricity price the project can afford.
Compare heating options and work out annual costs
If the electricity has no export value or other useful destination, removing the export cost improves this example by £52.50. Generator maintenance, equipment costs and any payment to the electricity owner still remain. Heat is given no value here because the source does not establish a usable heat supply.
For an annual estimate, use the miner electricity expected during hours when running makes sense. Scale the contribution by annual miner kWh divided by 1,000, then deduct fixed annual costs. Recalculate if electricity prices, mining income or usable heat change.
Simple payback is the total installed cost divided by positive annual cash contribution. There is no payback under a scenario with zero or negative contribution. The sources reviewed here do not provide the full project accounts needed to calculate an actual payback for this installation.
Record what the electricity would otherwise have earned
Instrument a pilot before scaling: record the surplus, export alternative and actual response of the mining load.
Record control signals, requested and delivered load changes, site imports and exports, and how the hardware restarts. Match the mining income to the same measurement intervals.
Questions worth asking
- Does the container consume imported electricity during shortfalls?
- Which results have been measured rather than stated as pilot objectives?
Try your own electricity and heat figures
Compare available miners and dated earnings estimates. Include heat only where you can use it or have a customer for it.
Sources and photographs
Sources checked on 29 September 2026. Project facts and quotations come from the publications below; the UK calculations and practical assessment are The Mining Shop’s analysis. This article is based on published material, rather than a site visit.
Photographs: RIVA GmbH Engineering, via Backnanger Kreiszeitung (source).
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