# Heating > Part of: [Climate](/climate.md) · Provider: [DutchGreenhouses](/) Heating delivers warmth where the crop needs it, circulating hot water through pipes laid at crop level that double as rails for the trolleys moving through the rows. A buffer tank separates when heat is made from when it is used, so warmth is produced cheaply and released when the greenhouse calls for it. ## Facts | Property | Value | |---|---| | Pipe rail heat output at 50/40 °C flow and return | 62 W/m² | | Pipe rail heat output at 70/40 °C flow and return | 85 W/m² | | Pipe rail net density | 13 km of pipe per hectare | | Minimum pipe temperature in Dutch practice | 40–45 °C | | Heat demand of a reference unlit tomato crop | 35.4 m³ gas-equivalent/m² per year | | Heat buffer sizing | 100–200 m³ per hectare | | Geothermal doublet depth | 2000–3000 m | | Minimum geothermal delivery temperature for direct greenhouse use | from 60 °C | Climate # Heating. Warmth, delivered exactly where the crop needs it. ## Warmth, delivered exactly where the crop needs it Heating is often the largest single energy cost in a greenhouse, so how heat is produced, stored and delivered matters enormously to both the crop and the bottom line. The backbone of the Dutch approach is pipe-rail heating: hot water circulated through steel pipes laid at crop level, warming the plants from within the canopy where the heat is actually needed rather than from high above. Those same pipes do double duty as rails for the picking and maintenance trolleys that move through the rows, a neat example of one element serving two purposes. Delivering heat where it counts is only half the challenge; producing it economically is the other. Buffer tanks — large insulated hot-water stores — decouple heat production from heat demand, letting the boiler or CHP run when it is most efficient or when energy is cheapest and banking the warmth until the crop calls for it, often overnight. That flexibility is what allows a grower to heat around energy prices rather than being dictated to by them. Combined heat and power (CHP) takes the logic further. A CHP unit burns gas to generate electricity, and in doing so produces heat and CO₂ as by-products — all three of which the greenhouse can use: the heat goes to the pipe-rail and buffer, the CO₂ enriches the crop, and the electricity powers the lights and installations or is sold back to the grid. Making one fuel input yield three useful outputs is a large part of why high-tech greenhouses can be energy-efficient despite their appetite for warmth. Above all, heating is not run flat-out but computed continuously. Pipe temperatures are steered hour by hour against the climate target, the outside weather, energy prices and the position of the thermal screens, so the crop stays in its ideal band at the lowest possible cost. DutchGreenhouses® designs the heating system — pipe-rail, buffering, heat source and CHP integration — around the crop, climate and local energy market. Get in touch to design heating for your greenhouse. From the knowledge base ## Reads you might find interesting ceacultivationbusiness-case ### Grow Like a Pro: Starting Smart, Growing Strong How Grow Like a Pro combines smart farming, CEA technology and local partnerships for eco-friendly, profitable, pesticide-free greenhouse pr Read article education ### The Case for a College Greenhouse Why a college greenhouse belongs in the curriculum: teaching science, craftsmanship, business logic and sustainability, and preparing studen Read article education ### The Case for a High School Greenhouse Why every high school greenhouse matters: how it makes STEM tangible, builds responsibility and teamwork, and helps students discover their Read article education ### Greenhouses in Education: The Case for Schools Greenhouses in education reconnect students to reality — the full case for why every school, high school, college and trade program should h Read article historyconstruction ### The Origins of Greenhouse Horticulture: My Backyard A tour through greenhouse horticulture history: from 19th-century Westland fruit walls to the “City of Glass” and today’s international high Read article company ### DutchGreenhouses Rebranded: A New Corporate Identity Announcing our new corporate identity — a visual style reflecting our dedication to advanced, high-quality greenhouse projects and The Futur Read article ## FAQ **How are commercial greenhouses heated?** Through hot water circulated in steel pipes at crop level, warming the plants from inside the canopy rather than from above. Those same pipes carry the picking and maintenance trolleys, so the heating system doubles as the internal transport network. **Do greenhouses need to be heated?** Wherever the crop's target temperature falls below what the climate supplies, which covers most of northern Europe for most of the year. Heating is usually the largest single energy cost, so how heat is produced and stored decides much of the operating budget. **Which heat source should a greenhouse use?** The question is rarely price alone, because some sources also deliver carbon dioxide for the crop and some do not. A low-NOx boiler and a cogeneration engine both yield cleanable flue gas; geothermal, heat pumps and electric boilers yield heat only, leaving dosing to be bought in separately. **What are greenhouse heating pipes made of and how do they work?** Steel pipes, commonly around fifty millimetres, laid in pairs between the crop rows and fed with hot water from a mixing group. A hectare carries roughly thirteen kilometres of pipe, giving a fifth of a square metre of heating surface per square metre of floor. **Why does a greenhouse boiler have to be low-NOx?** Because its exhaust goes to the crop. Flue gas from the burner is cleaned and dosed into the greenhouse as carbon dioxide, and nitrogen oxides damage plants at concentrations far below any human exposure limit. The boiler is specified around what the crop tolerates, not around what the chimney may emit. **Can a greenhouse be heated without gas?** Yes, and the Dutch sector is moving that way through geothermal wells, residual heat from industry and heat pumps. Geothermal earns its place where the well delivers above roughly sixty degrees; below that the heat needs upgrading, and the well loop always stays separated from the greenhouse circuit by a heat exchanger. **Are electric boilers used in greenhouses?** On small projects, where the heat demand is modest enough for electricity to compete and the loss of flue-gas carbon dioxide is affordable. At production scale the missing dosing usually costs more than the simpler installation saves. **How does a heat buffer save energy?** It resolves a timing conflict. The crop wants carbon dioxide by day and warmth by night, so the burner runs in daylight to supply dosing, and the heat it makes at the same time is banked in an insulated tank and released after dark instead of being wasted. ## Related [Climate](/climate.md) · [Cooling](/climate/cooling.md) · [Humidity Control](/climate/humidity-control.md) · [CO2 Enrichment](/climate/co2-enrichment.md) · [Energy Screens](/screening/energy-screens.md) · [Pipe Rail Heating](/glossary/pipe-rail-heating.md) · [Hot Water Storage Tank](/glossary/heat-buffer.md) · [Grow Pipe](/glossary/grow-pipe.md) · [Geothermal Energy](/glossary/geothermal-energy.md) · [Low-NOx Boiler](/glossary/low-nox-boiler.md) · [Electric Boiler](/glossary/electric-boiler.md) · [CHP (Combined Heat and Power)](/glossary/chp-cogeneration.md) · [Monorail](/glossary/monorail.md) · [Snowmelt Heating](/glossary/snowmelt-heating.md) · [Bench Heating](/glossary/bench-heating.md) · [Tichelmann System](/glossary/tichelmann-system.md) · [Mixing Group](/glossary/mixing-group.md) · [Heat Exchanger](/glossary/heat-exchanger.md) · [Heat Pump](/glossary/heat-pump.md) · [Flue Gas Condenser](/glossary/flue-gas-condenser.md) · [Tomatoes](/vegetables/tomatoes.md)