{ "meta": { "title": "D-Central — Home Heat-Reuse Application Compatibility Matrix", "description": "Compatibility matrix of 8 home heating applications for reusing Bitcoin ASIC miner waste heat — feasibility, achievable temperature range, air-vs-immersion requirement, plumbing/ducting complexity, BTU sizing rule-of-thumb and caveats per application.", "generated": "2026-06-23T18:44:25+00:00", "version": "1.0", "license": "https://creativecommons.org/licenses/by/4.0/", "license_name": "CC BY 4.0", "source": "https://d-central.tech/miner-heat-reuse-applications/", "record_count": 8, "provenance": "Physical anchor: a Bitcoin ASIC is a ~100%-efficient resistive heater; 1 kW electrical ≈ 3,412 BTU/h of heat. Per-application feasibility/temperature/complexity grounded in standard HVAC + hydronic engineering and D-Central heat-reuse, ventilation and immersion-cooling guidance.", "disclaimer": "A PLANNING reference, NOT an engineering sign-off. Final sizing, fluid selection, potable/electrical separation, permitting and installation must be done by a licensed mechanical/electrical professional. Mining fluids and potable/pool water must never mix; high-current electrical near water demands proper bonding and GFCI." }, "rows": [ { "id": "forced-air-space-heat", "application": "Forced-air space heat (direct room exhaust)", "feasibility": "High — the default, lowest-cost reuse", "temp_range": "Exhaust air ~35–50 °C (95–122 °F); typically 15–30 °C above room ambient", "medium": "Air-cooled miner. Exhaust ducted or blown directly into the occupied room; no liquid loop.", "complexity": "Low — a flexible duct / shroud and an intake filter. No plumbing.", "btu_rule": "Heat output (BTU/h) ≈ miner watts × 3.412. A 3,000 W miner ≈ 10,200 BTU/h — enough to heat roughly 300–1,000 sq ft depending on insulation and climate (≈10 BTU/h·ft² mild, 30–40 BTU/h·ft² cold).", "caveats": "Noise (70–75 dB raw) is the binding constraint indoors — needs acoustic shrouding/box. Dry winter air; dust/lint shed from the airstream. Provide outdoor makeup air. Never recirculate exhaust back through the intake.", "source": "ASIC = ~100% resistive heater; 1 kW = 3,412 BTU/h. D-Central heat-reuse + ventilation guidance.", "last_verified": "2026-06" }, { "id": "ducted-whole-room", "application": "Ducted whole-room / whole-home (into HVAC)", "feasibility": "Medium-High — works where ductwork and static-pressure budget allow", "temp_range": "Delivered air ~30–45 °C (86–113 °F) at registers after duct mixing/loss", "medium": "Air-cooled miner tied into supply/return ductwork or a dedicated plenum; a bypass damper sheds heat outdoors in summer.", "complexity": "Medium — sheet-metal transitions, a damper, and a booster fan sized to the duct static pressure. Often a mechanical permit.", "btu_rule": "Same 3.412 × watts. Two 3,400 W miners ≈ 23,000 BTU/h ≈ a small furnace stage. Do not exceed the duct's CFM/static-pressure rating or you choke miner cooling.", "caveats": "ASIC exhaust is cooler than furnace air, so it supplements rather than replaces a furnace. Add filtration to keep dust out of the duct system. Interlock a summer-bypass so you never push 10k+ BTU/h into a cooled house. Code may require a listed transfer assembly.", "source": "Heat balance from electrical draw; standard residential duct sizing. D-Central ventilation guide.", "last_verified": "2026-06" }, { "id": "immersion-hydronic-radiant", "application": "Immersion → hydronic radiant (in-floor / panel)", "feasibility": "High for LOW-temperature hydronic; the best match for immersion heat", "temp_range": "Dielectric fluid ~45–65 °C (113–149 °F); water loop ~40–55 °C after the heat exchanger — squarely in the low-temp radiant band (30–45 °C supply)", "medium": "Single-phase immersion REQUIRED. Dielectric fluid → liquid-to-liquid (plate) heat exchanger → closed glycol/water hydronic loop.", "complexity": "High — dielectric tank, circulation pumps on both sides, plate heat exchanger, expansion tank, manifolds. Licensed hydronic install.", "btu_rule": "3.412 × watts of captured heat. A 10 kW immersion tank ≈ 34,000 BTU/h — enough for ~800–1,500 ft² of in-floor radiant; size the loop to deliver that at ≤45 °C supply.", "caveats": "Low-temp radiant is the ideal sink because it WANTS the modest 40–55 °C immersion delivers; high-temp baseboard/fan-coil will under-perform. Maintain dielectric fluid (dielectric oil or engineered fluid) and seals. Keep mining and potable/hydronic fluids fully separated. Buffer tank smooths on/off cycling.", "source": "Single-phase immersion fluid temps; low-temp hydronic design band. D-Central immersion + heat-reuse guidance.", "last_verified": "2026-06" }, { "id": "dhw-preheat", "application": "Domestic hot-water (DHW) PREHEAT", "feasibility": "Medium — preheat only, never the sole water heater", "temp_range": "Captured water ~40–55 °C (104–131 °F): raises incoming cold mains, but below the 60 °C anti-Legionella / delivery target", "medium": "Single-phase immersion preferred (steady fluid temp). Double-wall (potable-rated) heat exchanger → preheat tank feeding the real water heater.", "complexity": "Medium-High — preheat tank, double-wall HX, tempering/mixing valve, backflow protection. Plumbing permit; potable separation is mandatory.", "btu_rule": "Heating water from 10 → 50 °C needs ≈ 2.7 kWh per 60 L (16 US gal). A 3 kW miner's ~10,200 BTU/h can preheat a household's daily draw, cutting the water-heater's run-time, not eliminating it.", "caveats": "MUST use a double-wall heat exchanger and never let mining fluid contact potable water. The downstream heater MUST still reach 60 °C for Legionella control. Mixing/tempering valve at the tap to prevent scald. Treat as energy recovery, not a code-compliant water heater.", "source": "Water-heating energy (4.186 kJ/kg·K); Legionella 60 °C guidance; potable double-wall HX requirement.", "last_verified": "2026-06" }, { "id": "greenhouse-grow", "application": "Greenhouse / grow space", "feasibility": "High — heat AND CO₂-free warmth where plants want 15–25 °C", "temp_range": "Target air 15–27 °C (59–81 °F); ASIC exhaust easily holds a greenhouse above freezing on cold nights", "medium": "Air-cooled (direct exhaust) is simplest; immersion → hydronic bench/soil heat for finer control and humidity management.", "complexity": "Low (air) to Medium (hydronic bench loop). Add a thermostat/damper to vent surplus heat on sunny days.", "btu_rule": "3.412 × watts vs. the greenhouse heat-loss load (glazing U-value × area × ΔT). A 3 kW miner ≈ 10,200 BTU/h covers a small hobby greenhouse through most of a temperate winter night.", "caveats": "Watch humidity — warm moving air dries plants; pair with humidity control. Filter dust off foliage. Provide fresh-air makeup. Over-temp venting needed for sunny days. Air exhaust adds NO CO₂ (electric, not combustion) — a plus over gas heaters.", "source": "ASIC heat output vs greenhouse glazing heat-loss; horticultural setpoints.", "last_verified": "2026-06" }, { "id": "workshop-garage", "application": "Workshop / garage / shop heat", "feasibility": "High — noise-tolerant spaces are the sweet spot", "temp_range": "Exhaust air ~35–50 °C (95–122 °F); holds a shop at 12–20 °C in winter", "medium": "Air-cooled, direct forced-air exhaust into the space. No liquid loop needed.", "complexity": "Low — a shroud and an intake filter; optional thermostat-controlled bypass to outdoors.", "btu_rule": "3.412 × watts. A 3,400 W miner ≈ 11,600 BTU/h ≈ a small garage heater — comfortably warms a 1–2 car insulated garage. Add miners for larger/leakier shops.", "caveats": "Best home for raw ASIC noise (a shop tolerates 70+ dB). Keep the airstream away from combustibles, finishes and dust-sensitive work. Provide makeup air. Dust-prone shops need better intake filtration to protect the miner.", "source": "ASIC heat output; typical garage/shop heating loads.", "last_verified": "2026-06" }, { "id": "pool-spa", "application": "Pool / spa / hot-tub heat", "feasibility": "Medium-High — a large, forgiving thermal sink", "temp_range": "Captured water 40–55 °C into the loop; pool target 26–29 °C (79–84 °F), spa 38–40 °C (100–104 °F) — both within reach", "medium": "Single-phase immersion → titanium/cupronickel plate heat exchanger → pool/spa circulation loop (corrosion-rated for chlorinated/salt water).", "complexity": "Medium-High — corrosion-resistant HX, pump tie-in, controls. Pool plumbing/electrical permit; bonding/GFCI critical near water.", "btu_rule": "3.412 × watts. Pools are huge sinks: a 5 kW miner ≈ 17,000 BTU/h trims a pool heater's run-time and extends the swim season; a spa (small volume) can be largely miner-heated.", "caveats": "Use a corrosion-rated heat exchanger (titanium for salt/chlorine) — ordinary steel/copper fails fast. Strict potable/electrical separation and equipotential bonding near water. A large pool needs many kW to move the temperature; treat the miner as a heat-recovery booster, not a primary pool heater.", "source": "ASIC heat output; pool/spa setpoints; corrosion-rated HX practice.", "last_verified": "2026-06" }, { "id": "food-dehydration", "application": "Food / lumber / produce dehydration", "feasibility": "Low-Medium — possible, but food-safety and temperature limit it", "temp_range": "Raw exhaust ~35–50 °C (95–122 °F) suits low-temp drying (herbs, lumber, jerky cure 40–50 °C); most food drying wants 50–70 °C, the high end of what a miner delivers", "medium": "Air-cooled exhaust through a CLEAN, FILTERED ductwork into a separate drying chamber — never the raw dusty airstream over food. Immersion-to-air HX gives controlled, particle-free heat.", "complexity": "Medium — a sealed drying chamber, fine filtration (or an indirect air-to-air HX), and temperature control.", "btu_rule": "3.412 × watts of low-grade heat; ample airflow already present. Match chamber airflow to the load so humidity is carried off, not just heated.", "caveats": "FOOD SAFETY: ASIC exhaust carries dust/lint and trace outgassing — do NOT blow raw miner air directly over food. Use an indirect heat exchanger or heavy filtration. Temperature tops out near 50 °C, marginal for safe meat drying (which often needs 60 °C+). Lumber/herb drying is the realistic use.", "source": "ASIC exhaust temperature ceiling; dehydration setpoints; food-safety isolation requirement.", "last_verified": "2026-06" } ] }