1. What is an Air Source Heat Pump Calculator?

Definition: This calculator estimates the operating cost of an air source heat pump (ASHP) based on heat load, COP, and electricity price.

Purpose: It helps UK homeowners and installers understand the running costs of ASHPs compared to traditional heating systems.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( \text{Cost} \) — Operating cost in pounds (£)
• \( \text{Load} \) — Heat energy required (kWh)
• \( \text{COP} \) — Coefficient of Performance (dimensionless)
• \( \text{Price} \) — Electricity price (£/kWh)

Explanation: The heat load is divided by the COP to get electrical energy consumed, then multiplied by electricity price to get cost.

3. Importance of ASHP Cost Calculation

Details: Accurate cost estimation helps in budgeting, comparing with gas boilers, and understanding seasonal variations in running costs.

4. Using the Calculator

Tips: Enter your heat load in kWh (annual or seasonal), typical COP (default 3.5), and current electricity price (default £0.34/kWh).

5. Frequently Asked Questions (FAQ)

Q1: What is a typical COP value?
A: COP typically ranges from 2.5-4.0 depending on outside temperature and system efficiency. 3.5 is a good average for UK conditions.

Q2: How do I find my heat load?
A: Use heat loss calculations from an energy assessment or your current gas usage (1 kWh gas ≈ 1 kWh heat).

Q3: Does this include installation costs?
A: No, this only calculates operating costs. Installation is a separate upfront cost.

Q4: How does this compare to gas heating?
A: Compare with (Load × Gas Price). ASHP is cheaper when (Gas Price) > (Electricity Price)/COP.

Q5: Should I use time-of-use tariffs?
A: ASHPs work well with off-peak tariffs (like Economy 7) to reduce operating costs further.