Should I Install Solar Before or After a Heat Pump?

A practical look at the best order for installing these two technologies.

Many homeowners want both a heat pump and solar PV. One of the most common questions is whether it’s better to install the solar first, the heat pump first, or both at the same time.

There’s no single right answer — it depends on your budget, how much disruption you can handle, and your long-term plans.

Installing Solar and Heat Pump at the Same Time

Advantages

• Only one period of disruption
• Easier to design the systems to work well together
• Potential cost savings on scaffolding, electrical work, and project management
• Can take advantage of the heat pump grant at the same time

Disadvantages

• Higher upfront cost all at once
• More complex project management
• If you change your mind about one technology, it’s harder to adjust

Installing One Before the Other

Installing Solar First

Many people install solar before a heat pump. This can be a good approach if:

• You want to reduce electricity bills quickly
• You’re not yet ready to commit to a heat pump
• You want to spread the cost over time

The downside is that you may need to adjust or upgrade the solar system later when the heat pump is installed, as your electricity usage pattern will change.

Installing Heat Pump First

Some people prefer to get the heat pump installed first. This can make sense if:

• Your boiler is old and needs replacing soon
• You want to improve comfort and reduce carbon emissions quickly
• You’re eligible for the heat pump grant now

The downside is that you won’t benefit from solar generation while you still have higher electricity usage from the heat pump.

Our View

If your budget allows and you’re planning to do both, installing them at the same time is usually the most efficient approach. It allows the systems to be designed together and minimises disruption.

However, if you need to spread the cost, installing solar first is often the more practical route for most homeowners. You can still add a heat pump later without major issues.

Thinking about installing both a heat pump and solar?

Use our Combined Estimator to see realistic costs and performance when installing multiple technologies together.

Try the Combined Estimator