What’s the future for Solar PV following recent Feed in Tariff(FiT) cuts?

Why you should use the electricity you generate on site yourself

Let’s be clear, Solar is, and always has been, a great way for homeowners & businesses to save money.

However, over the last 6 years, the Solar PV industry and consumers have focussed onSolar PV and the FiT from an investment and ROI perspective. Both the industry and customers should now view the benefits of solarpv differently; primarily as an environmental sound and sustainable source of low cost energy for consumers.

There’s a growing realisation among residential and business consumers that the key to maximising the benefits of Solar PV systems is to consume as much of the Solar PV electricity generated on-site as possible, because avoiding energy costs now has a higher return on investment than the FiT:

  • The FiT pays the Solar PV electricity generator 6.8p for 1kWh, depending on the system size


  • The savings from not buying 1kWh(unit) at 15p/kWh are more than twice this.

Most electricity suppliers increase their prices annually, by around 5%. Solar PV generated electricity is a fixed cost for the life of the system, so the PV owner is also hedging against future price rises over the 30-year life of their system.

So, how can Solar PV owners maximise their consumption of Solar PV electricity?

There are a number of options available to help consume Solar PV generated electricity rather than let it flow back to the national grid.

One technology that is gaining increasing popularity is battery storage.  People are curious about how they can store or use electricity rather than letting it return to the grid.  They know about batteries, so increasingly it’s something that comes up in conversation.  Most people are aware how mobile phone batteries have improved in performance over the last few years and how Tesla and other electric car manufacturers are using similar Li-ion technology to power their electric cars.

However, Li-ion technology is expensive on the scale required to store any meaningful amount of electricity for use when the Solar PV stops generating.

Many of our battery storage customers start-off looking at Li-ion but tend to opt for lead acid batteries in the knowledge that they have a useful life of approx 5 years during which time the price point of Li-ion batteries is expected to fall due to manufacturing scale and research.

People are very keen on immersion heater devices; they are an easy “add-on” to solar PV owners’ existing electrical systems.  They work by diverting electricity that starts to flow back to the national grid to heat water in the hot water storage tank, converting surplus solar PV energy to stored heat energy.

During the summer customers’ boilers tend to cycle when producing hot water in the morning & evening.  Many Customers switch off their boiler for the summer,which reduces wear & tear on it and let their solar PV system heat their water up.  The boiler’s still there for back-up if required.

Voltage Optimisation (VO) is a less well known technology where customers install a “step-down transformer” which reduces the incoming voltage from 240V to 230V in keeping with the rest of Europe. Most household appliances operate quite normally at this voltage and so will last longer than if they operate at a higher voltage.  There is also a potential reduction in electrical costs of 10% – 20% depending on what electrical goods are in regular use in the household.

Devices that help consumers increase their “self-consumption” of Solar PV generated electricity are increasingly popular with Solar PV owners who have got used to the return from their feed-in tariff but have come to realise they can improve the overall return from their Solar PV systems and the general energy efficiency of their homes by using more of the energy they are producing.

For more information on any system mentioned here, please get in touch today.

How to get hot water from your solar pv panels

Integrated Solar Photovoltaic (PV) systems and Hot Water Smart Switches

How can you use Solar PV generated electricity to heat water?

There are systems on the market which you can connect to your immersion heater and use excess Solar PV-generated electricity, which would otherwise be exported to the grid, to heat your water. These units monitor the amount of electricity generated as well as the amount that your home is using. When there is a surplus this energy is diverted to your immersion heater to heat water instead of being exported to the grid.

This type of system does not affect your FIT generation payments because you are still paid for exporting 50% of the electricity you generate regardless of whether you use it in your home or export it to the National Grid.

One of the Solar PV Smart Switches our Customers use.

Solar hot water switch

Here’s a Summary of how a Solar PV Hot Water Smart Switch works

  • The Smart Switch unit fits into your airing cupboard and connects to the immersion heater electrical supply; the example above measures 260mm x 130mm x 64mm.
  • The Smart Switch unit receives information continuously from a wireless sender device clamped over your house’s “live” supply cable.
  • The sender monitors the flow of electricity in and out of your house.
  • When there is surplus electricity flowing out of the house it tells the “Smart switch” to start using this surplus electricity to heat hot water.
  • This activates the system to start heating your water and adjust how much electricity is used to heat the hot water by only using the surplus energy generated by the Solar PV system – it doesn’t use any electricity from the National Grid.
  • It works with normal household immersion heaters rated up to 3kW. No modifications are needed.
  • You can override or program the unit for total flexibility.

No two households’ hot water use is the same, it depends on the number of occupants, how many showers they take, how long they shower for etc. Likewise the amount of solar PV electricity generated varies with the size of the Solar PV system and the amount of sunshine being converted into electricity at any one point in the day.

Hot water use and available electricity will affect how long it takes to achieve a return on the cost of the Smart PV switch. Below is a typical example of the costs and savings in an average UK home.

Typical cost savings from a PV solar hot water system*

  • The average house with a 4kWp Solar PV system is estimated to produce 3600kWhr of electricity a year and is deemed to export 50% of this annually.
  • The average hot water cylinder is 150 litres and the energy required to heat the water in it to 60 degrees C is approx 9kWh. If you pay 15p/kWhr for your electricity (inc standing charge & VAT), a tank of hot water would cost:

9kWh x 15 pence/ kWh = £1.35.

  • If you heat your hot water by electricity every day (at £1.35/day) this will cost £493/yr.
  • The Solar PV system is most productive during the April – Sept. It should provide enough surplus electricity for the smart switch to use to heat your hot water. So you will save ½ of £493, i.e. £246 a year. There will be surplus electricity which can be used by the smart switch Oct – Mar but possibly not enough to heat a whole tank.
  • Some days the tank will retain enough hot water to only need to be “topped-up” with Solar PV generated electricity.

An average cost to supply and fit a solar PV hot water switch with a Solar PV system is around £400. So in 2 years you will have recovered the cost of the unit and started to make significant savings on your hot water bills.

To talk to one of our Solar PV experts about a installing a photovoltaic system with a solar PV hot water switch, please call us now on 01480 819 740 or use our request a call back form.

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