🌱 Groundwater Heat‑Pump & Drip‑Irrigation System

Step‑by‑step calculation for using 15°C groundwater to pre‑heat a condenser and then irrigate crops.

Groundwater volume per year (m³):

Groundwater temperature (°C):

Temperature rise in pre‑condenser (ΔT in K):

How much the groundwater is warmed by the refrigerant.

Heat‑pump COP with pre‑heating:

Typical COP for two‑stage system with 15°C source: 4.0–5.0.

Select crop:

Target yield (kg/ha):

Typical yields: tomato 50–80 t/ha, lettuce 20–30 t/ha.

Geothermal borehole power (kW):

Operating hours per year (h):

Parameter	Value	Unit
Groundwater volume		m³/year
Heat extracted from water		kWh/year
Heat‑pump heating output		kWh/year
Equivalent boreholes saved		number
Irrigation water temperature		°C
Water required for selected crop		m³/ha
Area irrigable with available water		ha

🌿 Crop‑Specific Parameters (Reference)

Crop	Optimal root temp. (°C)	Water need (L/kg yield)	Drip‑line spacing (cm)
Tomato	18–22	15–20	30–40
Lettuce	15–18	10–15	20–30
Cucumber	20–24	18–25	40–50
Strawberry	16–20	12–18	20–30
Bell Pepper	20–22	20–25	40–50
Herbs	18–21	8–12	15–25

Groundwater at 15°C is pumped through a pre‑condenser, absorbing heat from the refrigerant.
The warmed water enters the main condenser, reducing the compressor’s temperature lift.
The heat pump delivers high‑temperature heat for greenhouse or floor heating.
The warm water (now ≈ 20–25°C) is stored and used for drip irrigation.
Each crop receives water at an optimal temperature and volume via automated drip lines.