Solar Inverter Types Explained: String, Microinverter, Hybrid and MLPE Compared (2026)
The inverter is the brain of your solar system. It converts DC electricity from your panels into 230V AC that your home can use, manages grid connection, and — in the case of hybrid inverters — controls battery storage. Choose the wrong inverter and you could lose 10–20% of your system's output to shading or face compatibility problems when adding a battery later.
This guide covers every inverter type clearly, what each is best for, and the key specs to compare before buying.
In this guide, you'll learn:
What a Solar Inverter Does
Solar panels produce DC electricity. Your home runs on 230V AC (50Hz in the UK and EU; 120V/240V 60Hz in the US). The inverter bridges this gap, performing two critical functions:
- Conversion: DC from panels → 230V AC at the correct frequency
- Maximum Power Point Tracking (MPPT): Continuously adjusts the operating voltage to extract maximum power from the panels as light conditions change throughout the day
Modern inverters also handle grid protection (anti-islanding — automatically disconnecting during a power cut to protect grid workers), monitoring (real-time output data), and in hybrid models, battery charging and discharging management.
Four Inverter Types: At a Glance
| Type | Where conversion happens | Shading impact | Best for | Cost (4kW system) |
|---|---|---|---|---|
| String inverter | Single central unit | High — worst panel limits all | Unshaded south-facing roofs | £500–£900 |
| Microinverter | Each panel individually | None — panels independent | Shaded or multi-orientation roofs | £1,200–£2,000 |
| Hybrid inverter | Central unit + battery port | Medium (string MPPT) | Systems with or planning battery storage | £900–£1,800 |
| String + optimisers (MLPE) | Central + per-panel DC optimisation | Low — each panel optimised | Partial shade, mixed orientations | £900–£1,500 |
String Inverters
A string inverter connects a series of panels (a "string") to a single central inverter. It is the standard choice for simple installations and represents 70–75% of all residential UK solar installations.
How shading affects string inverters: In a series string, the lowest-performing panel limits the output of all panels in that string. A single panel partially shaded by a chimney or tree can reduce the entire string's output by 30–60%. This is the primary limitation of string inverters and the reason to consider alternatives on shaded roofs.
Modern string inverters have multiple MPPT inputs — a dual-MPPT inverter can handle panels on two different roof orientations (e.g. south and east) independently. Check how many MPPT inputs your chosen inverter has before specifying panel placement.
When to choose a string inverter: Unshaded south-facing roof with all panels on one pitch. Simple, proven, cheapest option.
Microinverters
A microinverter mounts directly behind each panel and converts that panel's DC output to AC independently. Panels are wired in parallel at AC, so each operates entirely independently — shading on one panel has zero impact on others.
The advantages are significant on complex roofs: a microinverter system on a roof with chimneys, skylights, or panels on multiple orientations typically generates 10–25% more electricity annually than a string inverter on the same roof.
The limitations: higher upfront cost, more units to maintain (one per panel), and the inverters are on the roof where access for servicing is less convenient. For balcony and plug-in solar systems, microinverters are the only practical choice — see the microinverter comparison guide →
When to choose microinverters: Shaded roof, panels on multiple orientations, future panel expansion likely, or balcony/plug-in systems.
Hybrid Inverters
A hybrid inverter performs all the functions of a string inverter and also manages battery storage — charging the battery from solar surplus and discharging it to household loads when needed, all in one unit. Modern hybrid inverters also handle grid export and time-of-use tariff optimisation automatically.
Choosing a hybrid inverter from the start, even if you are not adding a battery immediately, future-proofs your system. Adding a battery to a standard string inverter system later requires either replacing the inverter or adding a separate AC-coupled battery inverter — both add cost. A hybrid inverter ready for battery connection typically costs £300–£500 more than a standard string inverter.
When to choose a hybrid inverter: Planning to add battery storage now or in the next 5 years. Also best for EV charging optimisation and time-of-use tariff management.
MLPE: Power Optimisers
Module-Level Power Electronics (MLPE) — typically SolarEdge power optimisers — attach to each panel DC-side and optimise each panel independently before feeding a standard string inverter. The result is per-panel performance independent of shading, without the full cost of microinverters.
SolarEdge is the dominant brand in this category. Their system requires both optimisers (fitted to each panel at installation) and a compatible SolarEdge inverter. The inverter operates at a fixed voltage regardless of panel output variation, which gives better shading performance than a standard string inverter.
Cost is between string and full microinverter: typically £300–£600 more than a string inverter alone for a 4kW system, versus £600–£1,100 more for full microinverters.
When to choose MLPE: Partial shading that doesn't justify full microinverter cost, or when per-panel monitoring and rapid shutdown compliance (required in some US states) is needed.
Which Inverter Is Right for You?
| Your situation | Recommended inverter | Why |
|---|---|---|
| Simple south roof, no shading, no battery plans | String inverter | Cheapest, proven, fully adequate |
| Simple south roof, battery now or soon | Hybrid inverter | Future-proofs; modest premium |
| Shaded roof or multiple orientations | Microinverter or MLPE | 10–25% more generation from shaded panels |
| Balcony or plug-in solar (1–4 panels) | Microinverter | Only practical option for single-panel systems |
| Large system, complex roof, maximum monitoring | Microinverter | Full panel-level data, no single point of failure |
Best Inverter Brands in 2026
Brands with strong UK market presence, good warranty support, and proven reliability:
- Solis (string/hybrid): Best value for money. 5-year warranty standard, 10-year with registration. Widely used in UK residential market.
- Huawei SUN2000 (string/hybrid): Excellent monitoring app (FusionSolar), strong warranty, very efficient. Some political considerations for government/commercial sites.
- SolarEdge (MLPE system): Market leader in optimiser systems. Strong monitoring, 12-year warranty on inverter. Premium price.
- Enphase (microinverter): Best microinverter ecosystem, 25-year warranty, excellent monitoring. Most expensive per-panel option.
- GivEnergy (hybrid): UK-based support, good battery integration, competitive pricing. Strong for combined solar+battery systems.
- Victron (off-grid/hybrid): Industry standard for off-grid and van builds. Excellent build quality and compatibility. Premium price.
Installing battery storage? See the home battery storage guide for compatible battery and inverter combinations, real 2026 costs, and a clear payback analysis.
Trying to understand system costs? The solar panel cost UK 2026 guide covers installed prices for every system size and shows how inverter type affects the overall quote.
Frequently Asked Questions
What is the best solar inverter for a UK home?
For a simple unshaded south-facing roof without immediate battery plans: Solis or Huawei string inverter (£500–£900 installed). For battery storage planned: GivEnergy or Huawei hybrid inverter (£900–£1,500). For shaded or complex roofs: SolarEdge with optimisers (£1,200–£1,800) or Enphase microinverters (£1,500–£2,500). All of these are MCS-certified and eligible for SEG registration.
How long does a solar inverter last?
Standard string inverters last 10–15 years. Hybrid inverters 10–15 years. Microinverters 20–25 years (they carry 25-year warranties from Enphase and AP Systems). Budget for one string inverter replacement during a solar panel system's 25-year life — typically £600–£1,000 supply and fit.
String inverter vs microinverter: which is better?
String inverters are better value on simple unshaded roofs. Microinverters generate significantly more electricity on shaded or multi-orientation roofs and have longer warranties. On a south-facing unshaded UK roof the output difference is minimal — the string inverter's lower cost wins. On any roof with shading the microinverter pays back its premium within 3–5 years through higher generation.
