§ Archive · 9 files

System Guides

Find the right solar system for your roof and house size.

Find the Right Solar System for Your Home

Most solar guides give you generic advice. These guides do not. Each one is a worked example for a specific house size and roof orientation, with real component part numbers, string voltage checks, battery sizing, and ROI figures. Yield numbers come from PVGIS and three years of metered data across pitched, flat, and wall-mounted panels.

Every guide covers a budget option and a premium option, with three panel strategies each: best value (cheapest per watt), smallest footprint (fewest panels for tight roofs), and maximum overpanelling (lower-Voc panels to squeeze more onto each string). If you have not decided whether solar is right for your home yet, start here first.

Solar Energy Concepts System Rating

We score every system option against three metrics so you can compare at a glance:

Cost1 = accessible • 10 = premium only

12345678910

Consumption FitHow much of what you generate you actually use directly

LOWMIDHIGH

Tariff Exposure1 = ROI from self-consumption • 10 = depends on export rates

12345678910

A high-consumption household running a heat pump and EV will typically score low on tariff exposure (1-2) because they consume almost everything they generate. A system designed around Octopus Agile arbitrage with a large battery scores high (8-10) because the entire business case depends on half-hourly pricing staying favourable.

All Guides

System Guides

Maximum Number of Solar Panels Allowed in the UK: What Actually Limits You

There is no legal maximum number of solar panels allowed in the UK: standard homes are limited by practical constraints, not panel count.
Nine 400W panels make 3.6kWp: ten make 4kWp DC and can still use a 3.68kW G98 inverter.
Allow roughly 1.9m² per panel: then leave room for roof edges, ridges, valleys and obstructions.
G98 limits inverter capacity, not panel capacity: above 3.68kW AC on single phase, obtain G99 approval first.

Read Entry →

System Guides

Solar Panel Output by Month UK: What to Expect Through the Year

UK solar panel output is strongly seasonal: June and July normally peak, while December produces the least.
Winter output is a small part of summer output: November to February cannot be treated like four average months.
A battery cannot move summer electricity into winter: size it around daily surplus, not annual generation.
PVGIS provides the useful estimate: enter your location, roof direction, angle and system size rather than relying on one UK average.

Read Entry →

System Guides

Three-Phase Solar UK: A Homeowner’s Guide to G98, G99 and Inverters

Most UK homes have a single-phase supply, but some homes already have three phase.
G98 permits up to 3.68kW per phase, so a three-phase supply allows up to 11.04kW in total.
You can use a true three-phase inverter or, with DNO agreement, one single-phase inverter on each phase.
Three-phase solar makes most sense with a large array and substantial loads such as a heat pump and EV.

Read Entry →

System Guides

Can You Have Two Separate Solar Systems in the UK?

You can have two separate solar systems on one UK property: both systems must be declared and safely connected.
The DNO assesses their combined inverter capacity: two 2kW inverters count as 4kW, so a single-phase site normally needs G99 approval.
One boundary meter records the property’s net import or export: separate solar arrays do not normally need separate export meters.
An MCS system and a DIY expansion can coexist: keep their paperwork separate and check the export supplier’s evidence requirements.

Read Entry →

System Guides

Solar Panels for a 4-Bedroom House with South-Facing Roof

South-facing is the UK’s highest-yield orientation (978 kWh/kWp/year per PVGIS). Still easy to overbuild.
Battery is the single biggest ROI lever. Without it, 60%+ of the midday peak exports at 5-12p.
Budget 3.6kW + 12 panels + 5kWh battery (£3,550 DIY) pays back in 3.9 years at typical 4-bed consumption.
Premium 5kW + 16 panels + 16kWh battery only earns out above ~5,000 kWh/year.

Read Entry →

System Guides

Solar Panels for a 3-Bedroom House with East/West Roof

East/west roofs lose about 19% of annual yield vs south, but the demand-curve match is often better for a typical 3-bed household.
A battery turns the midday lull into evening savings. The single biggest ROI lever on this roof.
The budget 3.6kW DIY build is £2,400 and pays back in 3.2 years on a typical 3-bed.
The premium 5kW + 16kWh build only makes sense with a heat pump or EV.

Read Entry →

System Guides

Solar Panels for a 4-Bedroom House with NW/SE Split Roof

A 5.46 kWp NW/SE array models at about 4,253 kWh a year: that is 83% of the same panel area facing south in our PVGIS reference case.
The two roof faces need separate MPPT inputs: the SE and NW strings operate differently through the day.
At 25% direct use, the reference array is worth about £425 a year: this is an illustration using 25p import and 5p export, not a quote.
A battery is a usage decision, not an automatic requirement: estimate the extra shifted kWh before paying for storage.
Ask installers for a yield for each face: a single blended kWh/kWp figure can hide a weak NW design.

Read Entry →

System Guides

Solar Panels for a 2-Bedroom House with South-Facing Roof

South-facing 2-bed produces 978 kWh/kWp/year, the best case in the UK. Easy to over-build for a household that only uses 2,100 kWh/year.
The battery is where the ROI lives. Without one, south-facing midday surplus exports at 5-12p while you buy back at 28p.
Budget 3.6kW + 10 panels + 5.12kWh battery costs around £2,364 DIY and pays back in 3.5 years at typical 2-bed consumption.
Premium 5kW + 9.5kWh battery only earns out if you have a heat pump, EV, or both. Overkill for a low-consumption 2-bed.

Read Entry →

System Guides

Solar Panels for a 3-Bedroom House with North-Facing Roof

North roofs produce about 63% of south-facing yield per PVGIS. Not dead, but the economics only work in specific scenarios.
It pays back fast for high-consumption homes (heat pump, EV). It’s marginal for a 2,000-3,000 kWh household.
Budget 3.6kW + 12 panels + 5.12kWh battery costs £2,600 DIY and pays back in 4.6 years at typical consumption.
Premium 5kW + 16 panels + 16kWh battery only earns out if consumption is over 5,000 kWh/year.

Read Entry →