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: Bitcoin Brabant · Original source. Operator portrait from the retrospective; not a photograph of a currently operating greenhouse.
Renewables and heat reuse
Bitcoin Brabant describes moving industrial miners into a hydrangea greenhouse where heat was useful. Its retrospective explicitly says the family-run greenhouse operation ceased in 2023.
- Project at a glance
- Greenhouse pilot · now historical
- Source date and context
- 2022 pilot; operator update 10 April 2026
- 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 greenhouse trial that is now part of the past
Bitcoin Brabant moved industrial miners into a hydrangea greenhouse after a sharp increase in its electricity price. The grower could use the heat, and the operator developed protective casings for the machines. The later retrospective is unusually useful because it also records the limitations: few enquiries led to workable installations, and the family greenhouse operation ceased in 2023. It is a record of an earlier trial, rather than a current customer success story.
“Thousands of requests but almost zero business cases. Only a few were worth it and installed.”
Heat helped, but electricity still set the terms
Electricity→Bitcoin miners→warm air→greenhouse demand
A greenhouse needs the right temperature, humidity and airflow for its crop. Mining has to fit those requirements. The heat may reduce a fuel bill during a cold spell, but summer output may have little value. Crop prices, labour and rent also remain part of the grower's business, however well the heating equipment performs.
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
£51.905.19p 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 | 60% of miner electricity = 600 kWh; valued at 6p per delivered kWh |
| 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 | Without heat value | With useful heat |
|---|---|---|
| 5p | −£13.50 | £22.50 |
| 8p Chart example | £15.90 | £51.90 |
| 11p | £45.30 | £81.30 |
- Mining income needed to cover running costs
- 2.70pper miner kWh
- Highest electricity cost or export value supported
- 9.94pper 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
Use the heating system you would actually choose as the comparison. For example, a heat pump using electricity at 20p/kWh with a seasonal COP of 3 has an electricity cost of about 6.67p per kWh of heat. A resistance heater at that tariff uses 20p per kWh of heat. These are calculation examples, rather than measurements from this project.
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.
Check the growing business as well as the miners
Cheap electricity and a nearby heat customer must coincide for the business case to work.
Build a monthly crop-and-energy budget. Record usable heat separately from heat vented outside; keep the economics of growing and computing visible as distinct activities.
Questions worth asking
- Can the crop tolerate mining interruptions?
- How much summer mining heat has no useful destination?
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: Bitcoin Brabant (source).
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