South-facing roofs get most of the attention in solar guides — and for good reason, they do produce the most total annual energy. But a large proportion of UK homes have roofs that run east to west, or are partially east and partially west-facing. The good news is that an east-west solar installation not only works — it has some genuine advantages that a single south-facing array doesn’t.
What Is an East-West Solar Panel Configuration?
An east-west system splits the solar array across both roof slopes — panels on the east face generate power from morning light, panels on the west face generate power from afternoon and evening light. Instead of a single large peak of generation around midday, you get a longer, flatter generation curve that spans more of the day.
How Does East-West Generation Compare to South-Facing?
A south-facing array at 35-degree pitch in the UK will generate the highest total annual output per panel. An east-west array on the same roof will generate approximately 10–15% less total energy across the year. However, the generation profile is fundamentally different:
For many homeowners, this flatter profile is actually more useful — because it aligns better with when electricity is actually consumed.
What Are the Advantages of an East-West Solar System?
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Better morning generation — East panels are producing well when south-facing panels haven’t yet reached meaningful output. If you run appliances in the morning, this is directly valuable.
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Extended afternoon generation — West panels continue producing into late afternoon and early evening, which is often the highest consumption period of the day.
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Higher self-consumption without battery — A flatter generation curve means a larger proportion of your generation falls during active household use, reducing the proportion you export.
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More total panel capacity — Using both roof slopes means you can install more panels in total, increasing system size without needing a single large south-facing plane.
Does an East-West System Work Well With Battery Storage?
Yes, though the interaction is slightly different from a south-facing system. A south-facing array creates a large midday surplus that charges a battery quickly. An east-west array generates more consistently, which means the battery charges more gradually across the day. Depending on your consumption pattern, this can actually result in more efficient battery use — you’re drawing from the battery less during the day because the panels are generating more evenly throughout.
What Inverter Setup Is Needed for an East-West System?
This is an important technical consideration. A standard string inverter connects all panels in a series — if the east and west panels are on the same string, the lower-performing array at any given time will reduce the output of the higher-performing one. To avoid this, east-west systems should use one of the following:
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Two separate string inverters or two MPPT inputs on a single inverter — Most modern hybrid inverters (compatible with Tesla Powerwall, Fox ESS, and other battery systems) include dual MPPT inputs for exactly this purpose
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Microinverters — Each panel operates independently, completely eliminating inter-panel shading and orientation losses
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DC optimisers with a string inverter — Panel-level optimisation without the full cost of microinverters
HomeKog’s MCS-certified engineers specify the right inverter configuration for your roof layout during the survey — it’s not a detail to leave to chance.
Can You Mix Orientations on the Same Roof?
Some roofs are more complex — L-shaped properties, hipped roofs, or properties with both a south-facing main slope and an east or west-facing secondary slope. These configurations are perfectly workable and often benefit from the same dual MPPT or microinverter approach. A thorough survey will map all available roof planes and model the generation from each.
The Part Nobody Talks About: East-West Systems and Time-of-Use Tariffs
If you’re on a time-of-use energy tariff — where electricity costs more at peak times (typically 4pm–7pm) — an east-west solar system has a specific advantage that a pure south-facing array doesn’t: west-facing panels generate electricity during the expensive peak window.
In summer, west-facing panels can still be producing 1–3 kWh during the early evening hours when your tariff is at its most expensive. This means you’re directly displacing the most costly electricity you’d otherwise buy, rather than generating a midday surplus when rates are lower.
Combined with a battery, an east-west system with a time-of-use tariff can be optimised to minimise peak-rate grid consumption almost entirely during the summer months. It’s a combination that south-facing-only systems simply can’t replicate in the same way.
Frequently Asked Questions
Q: Can north-facing roof panels ever work?
In the UK, north-facing solar panels are generally not recommended. A true north-facing slope will generate significantly less than any east, west, or south orientation — potentially less than 50% of a comparable south-facing installation — and the financial case rarely stacks up. There are exceptions for very flat roof angles, where a north-facing tilt has minimal penalty, but these are assessed case by case.
Q: Does a dual-roof installation cost more than a single-slope system?
An east-west system with the same total number of panels as a south-facing array costs broadly the same for the panels themselves. The potential additional cost comes from the inverter specification — dual MPPT inputs or microinverters can add to the budget compared to a simple string inverter. HomeKog will provide a transparent breakdown of these costs in your quote.
Q: Will an east-west system affect my SEG export rate or eligibility?
No. The Smart Export Guarantee pays you based on how many units you export to the grid, regardless of your panel orientation or system configuration. An east-west system that generates slightly less total annual output will export slightly less — but because it tends to have higher self-consumption, the reduction in export income is typically offset by higher direct bill savings.
