Many of our customers have installed an iBoost or Immersun or similar to divert excess solar PV into their hot water tank.
If you have an electric vehicle (EV), it makes sense to divert excess electricity into the EV battery. In fact if your hot water is heated by gas, oil or biomass, it makes more sense to charge the car than it does to charge the hot water tank. An iBoost is generally displacing fuel costing ~ 5p per kWh, and so 1kWh of diverted electricity is worth ~ 5p. Charging the EV displaces grid electricity at the ‘full value’ ~ 15p per kWh.
zappi is an EV charging point with special eco charging modes to optimise self-consumption of on-site solar PV, wind etc. Specifically it has three charging modes:
By setting the Min Green Level to 100%, the car will be charged using only surplus renewable power, providing there is sufficient surplus power to do so.
Note: The EV charging standard does not support charging below 1.4kW.
To supplement the ECO and ECO+ modes, there are various optional boost functions, designed to ensure your car achieves minimum levels of charge whatever the weather. More on these below.
How much does zappi cost? Only £150 more than a standard charger...
The average cost of a zappi installed is £900 - £1000, depending on cabling requirements. This is about £150 more expensive than a standard charger. The zappi is OLEV approved and therefore eligible for the OLEV grant of £500. You can claim the OLEV grant if you have proof of purchase of an electric vehicle on the eligible vehicle list (must cost less than £60,000).
eddi is similar to an iBoost or Immersun, in that it diverts excess solar generation to the hot water tank. If you install zappi and eddi, you can choose whether to prioritise zappi or eddi.
zappi responds quicker than the iBoost or Immersun, and so the default will be that zappi will be switched on before the iBoost or Immersun. If you don’t want this to happen, you can set a delay on the zappi to give the iBoost or Immersun time to turn on.
If you have a dc coupled battery system, the battery will always take priority over the zappi. If you have an ac coupled system (e.g. Tesla Powerwall 2), the battery system is likely to have a similar response time to zappi. Therefore you need to set a delay on the zappi if you want to prioritise charging of your battery over your zappi. If you want to prioritise the zappi over the battery there is a ‘workaround’ we can install using a CT clamp – this will tell the zappi when the battery is being charged, thus turning on the zappi, subject to sufficient power availability.
To supplement the ECO and ECO+ modes, there are various optional boost functions, designed to ensure your car achieves minimum levels of charge whatever the weather.
zappi’s a great product with all bases covered – just what you need if you drive an EV and you want to optimise the use of your solar. It is supplied at a very modest premium to the cost of a standard charger, and qualifies for the OLEV grant where relevant.