Do I need a hot water cylinder?

Yes — Eddi heats water in a cylinder via an immersion element. If you have a combi boiler (no cylinder): you'll need to install one (£300-£500). This is still worthwhile — the combined payback is 3-5 years.

Can Eddi replace my gas boiler for hot water?

In summer: yes — Eddi + solar provides 100% of hot water needs. In winter: 20-30%. Annual average: 50-60% of hot water from solar. Your gas boiler still provides backup in winter.

Does it work with any solar system?

Yes — Eddi works with any solar installation. It doesn't connect to your inverter — it measures grid export via a CT clamp. Brand, size, and type of solar system don't matter.

Can I have two heater outputs?

Yes — Eddi has two heater connections. Priority heating: immersion first, then a second load (e.g., towel rail, storage heater, or second cylinder). Both are proportionally controlled.

myenergi Eddi Review

By Home Solar Guide Team|Updated 18 March 2026|comparison

Independently written | Evidence-based | Sources cited

Eddi diverter — Eddi: diverts surplus solar to your immersion heater. Free hot water from solar.

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Is the myenergi Eddi worth it?

myenergi Eddi review: WHAT IT DOES: diverts surplus solar electricity to your immersion heater (or any resistive load up to 3.68kW). Result: free hot water instead of exporting at 4.5p/kWh. HOW IT WORKS: CT clamp monitors grid export. When surplus solar is detected, Eddi proportionally powers the immersion — matching the available surplus exactly. PRICE: £400-£600 installed. SAVINGS: £100-£200/yr on gas/oil heating (replaces boiler hot water with solar-heated water). PAYBACK: 2-4 years. REQUIREMENTS: hot water cylinder with immersion element. Homes with combi boilers (no cylinder) need a cylinder installed (£300-£500 extra). MODES: (1) Normal — diverts any surplus. (2) Boost — forces heating regardless of solar (manual). (3) Timer — scheduled operation windows. VERDICT: simple, effective, fast payback. One of the best solar accessories available.

Frequently Asked Questions

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