How Much Do Solar Panels Cost in the UK?
The cost of a solar panel installation depends on more than the number of panels fitted to the roof.
System size is important, but the roof layout, access, electrical work, inverter specification and any battery storage can all change the final cost. Two homes using the same number of panels can therefore receive quite different quotations.
As a general benchmark, Energy Saving Trust currently puts the cost of a typical domestic 4.5kWp solar PV system at around £7,600. That is useful as a guide, but it should not be treated as the price every property will pay.
A proper quotation needs to be based on the property, the amount of electricity the household uses and the system being designed.
What Determines the Cost of a Solar Panel System?
The panels are only one part of a solar PV installation.
A complete system also requires an inverter, mounting equipment, electrical protection, cabling and monitoring. There may also be costs associated with scaffolding, electrical upgrades or more complicated roof layouts.
The main factors affecting the final price include:
- System size and number of panels
- Panel specification
- Inverter specification
- Roof type and layout
- Scaffolding and access
- Electrical work required
- Mounting system
- Battery storage
- Monitoring equipment
- Complexity of the installation
This is why two quotations for the same number of solar panels may not represent the same system.
How Does System Size Affect the Price?
Domestic solar PV systems are normally described by their peak generating capacity in kilowatt peak (kWp).
A larger system generally requires more panels, mounting equipment and installation work, so the initial cost will usually increase with system size.
However, fitting the largest system that will physically fit on the roof is not necessarily the right approach.
The system should be designed around factors including:
- Available roof space
- Roof orientation – Shading
- Household electricity consumption
- Expected solar generation
- How electricity is used throughout the day
- Any plans for battery storage
- Future electricity demand
Future demand can be particularly relevant if the household is considering an electric vehicle or heat pump. The aim is to specify a system that suits the property and its electricity requirements rather than choosing a panel quantity in isolation.
Does the Type of Solar Panel Affect the Cost?
Yes. Solar panels are available with different outputs, dimensions, warranties and specifications.
Higher-output panels can generate more power from a given roof area, which can be particularly useful where usable roof space is limited.
When comparing quotations, it is therefore important to look beyond the number of panels.
The quotation should identify the:
- Panel manufacturer
- Panel model
- Rated output
- Number of panels
- Total system capacity
- Product warranty
- Performance warranty
Ten panels of one specification do not necessarily provide the same installed capacity as ten panels from another range.
Can the Roof Affect the Installation Cost?
The roof can make a considerable difference to the work involved.
A large, accessible pitched roof with few obstructions will normally be more straightforward than a roof divided by dormers, chimneys, rooflights or several different elevations.
The roof covering also affects the mounting method. Installing solar panels on tiles, slate, standing-seam metal roofing or a flat roof requires different equipment and installation techniques.
Scaffolding and access also need to be considered.
This means the cost of installation cannot be determined accurately from the number of panels alone.
Does the Inverter Affect the Price?
The inverter is a key part of a solar PV system.
Solar panels generate direct current (DC) electricity. The inverter converts this into alternating current (AC) electricity that can be used within the property.
The inverter needs to be correctly specified for the solar array and the wider system.
Depending on the installation, the design may use a string inverter, a battery-compatible or hybrid inverter, microinverters, or equipment such as power optimisers.
The appropriate arrangement will depend on the system design, roof layout, shading and whether battery storage forms part of the installation.
When comparing solar quotations, the inverter specification should therefore be considered alongside the panels.
How Much Does It Cost to Add Battery Storage?
Battery storage increases the initial cost because it adds further equipment to the installation.
Energy Saving Trust currently gives an indicative cost of around £4,600 for a 5kWh battery, although actual prices vary according to manufacturer, capacity, specification and installation requirements.
The appropriate battery size depends on more than the size of the solar array.
Factors to consider include:
- Household electricity consumption
- Solar generation
- When electricity is used
- How much surplus solar electricity is available
- Battery usable capacity
- Import and export tariffs
- Whether the battery will also charge from the grid
It is also possible to add battery storage to an existing solar PV installation, although compatibility with the existing equipment needs to be checked.
Is There 0% VAT on Solar Panels?
Qualifying solar panel installations in residential properties currently benefit from a temporary 0% VAT rate.
Under the current rules, this zero rate applies until 31 March 2027.
Qualifying electrical battery storage is also included. This can apply when a battery is installed with solar panels, added to an existing solar installation or installed as a qualifying standalone system.
The installer is responsible for applying the correct VAT treatment to the work.
Should You Choose the Cheapest Solar Panel Quote?
The cheapest quotation is not necessarily the cheapest equivalent system.
Before comparing prices, check what each installer is actually proposing.
This should include:
- Total system capacity in kWp
- Panel manufacturer and model
- Panel output and quantity
- Inverter manufacturer and model
- Mounting system
- Monitoring
- Scaffolding
- Electrical work
- Product and installation warranties
- Estimated annual generation
- Battery capacity, where included
- Any work excluded from the quotation
A lower quotation may be for a smaller system, different equipment or a different scope of work.
Comparing the specification as well as the final price gives a much clearer picture.
How Much Can Solar Panels Save?
There is no single annual saving that applies to every household.
How much a solar PV system can save depends on how much electricity it generates and how that electricity is used.
Electricity generated and used within the home reduces the amount that needs to be bought from the grid. Surplus generation can be exported or stored in a battery for later use.
The financial result will depend on factors including:
- System size
- Roof orientation and shading
- Annual solar generation
- Household electricity consumption
- How much generated electricity is used within the property
- Electricity prices
- Export tariff
- Battery storage
- Initial installation cost
For this reason, estimated savings and payback should be calculated using the proposed system and the household’s circumstances rather than applying a general figure to every property.
Can You Get Paid for Exporting Solar Electricity?
Surplus electricity that is not used or stored can be exported to the electricity grid.
Under the Smart Export Guarantee (SEG), participating electricity suppliers offer eligible small-scale generators payment for electricity exported to the grid.
There is no single national SEG rate. Suppliers set their own tariffs and terms, so the amount received will depend on the export tariff and how much electricity is actually exported.
Homes with battery storage may use more of their solar electricity themselves rather than exporting it immediately.
Whether storing or exporting surplus generation provides better value will depend on the household’s electricity use, battery setup and available tariffs.
Are There Grants for Solar Panels?
There is currently no single solar panel grant available to every homeowner in the UK.
Solar PV can be included within certain targeted energy-efficiency schemes for eligible households, but the qualifying criteria vary.
Government support can also change, so homeowners should check the current rules before making a decision based on a particular grant or funding scheme.
The current 0% VAT treatment for qualifying residential solar installations is separate from a grant.
Getting an Accurate Solar Panel Quote
Online prices can provide a useful indication of what solar panels may cost, but an accurate quotation needs to take the individual property into account.
A solar assessment should consider the available roof area, orientation, shading, electrical installation, household electricity consumption and any plans for battery storage or increased electricity demand.
The resulting quotation should make clear what equipment is proposed, the size of the system, its estimated generation and what is included within the installation price.
Renewable Planet designs and installs residential solar PV and battery storage systems. A property assessment can establish what can be installed, the appropriate system size and the expected generation before a final quotation is provided.