How much useful heat is needed?
Use an explicitly bounded gable heat-loss scenario. Do not confuse a model’s thermal output with an appliance’s electrical input or a certified installation design.
Estimate a heating load →Research & buying hub
Heating & ventilation
Estimate heat loss, operating cost and airflow without confusing a planning calculation with a complete system design.
Choose the next step by your constraint.
A useful shortlist starts with the question the purchase must answer, not a generic “best” label.
What could the electricity cost?
Enter electrical input, enabled hours, assumed duty cycle and your tariff. The result is a scenario, not a prediction of weather or runtime.
Calculate an energy-cost scenario →How much summer exhaust airflow?
Keep air changes per minute separate from winter leakage per hour. Use the stated design-volume method before checking actual fan performance and system resistance.
Estimate the airflow target →Keep the calculation connected to the purchase.
Greenhouse Heater Sizing Calculator
Estimate steady-state heat loss for a simple rectangular gable greenhouse, with each assumption visible.
Open the tool →Greenhouse Heating Cost Calculator
Turn electrical input, running hours, duty cycle and your own tariff into an energy-cost scenario.
Open the tool →Greenhouse Ventilation / Fan Sizing Calculator
Estimate a summer exhaust-airflow target using the UMass floor-area and design-height method.
Open the tool →Compare assumptions before comparing heaters.
The 54-scenario greenhouse heating benchmark makes size, thermal inputs and temperature difference visible together. The downloadable data and reference arithmetic let you reproduce each modeled case. It is not measured equipment performance or a winter-bill forecast.
Greenhouse heater sizing: heat loss, output and running cost are different numbers
An explicit heat-loss example, the difference between thermal output and electrical input, and the limits of greenhouse heating estimates.
Read the guide →Greenhouse exhaust fan sizing: CFM, design volume and real airflow
Use the UMass summer ventilation method correctly, distinguish natural vents from fans and avoid per-minute versus per-hour mistakes.
Read the guide →Keep the research connected. Compare the exact kit records, then use the planning tools to expose the assumptions behind your decision.