Category Archives for "Renewable energy"

The Solar Battery – An Idiots Guide.

Solar Battery: An idiots guide

There have been several government schemes to increase the number of houses using Solar panels, with incentives offered to homeowners including free installation. Once solar panels are fitted you can reduce your electricity bill by harnessing the power of natural sunlight to produce energy. Whilst there is a wide range of solar panels available, one of the most important parts is often neglected; the storage of solar power.

solar panel battery

What is even better, is that you don’t need solar panels fitted to use solar batteries. If you are on an Economy 7 (night and day) tariff you could use solar batteries to store energy to use during peak times, paying the night tariff to charge them. However, let’s focus on using solar batteries linked to a solar panel system.

What are solar batteries & how do they work? 

Solar batteries store the energy produced by solar panels and many homeowners have been caught out by purchasing poor quality batteries and then not seeing the savings expected. By storing solar energy in a good quality battery, you not only save the power for when you need it, such as a cloudy day but reduce your bills even further. By storing energy for when you need it you don’t need to buy additional energy from your electricity provider. The free energy produced by solar panels lasts even longer!

Solar batteries help make homes even more self-sufficient and less reliant on the national grid for electricity. In an ideal world, every home would be self-sufficient, but we are a little way from that yet! With cuts to the benefits of Feed-In-Tariffs (how much you can be paid for the extra energy produced by solar panels), it makes even more sense to purchase a good quality solar battery and safeguard your future energy costs.


This is a great video explaining the concept & how the solar battery works 


What are the best solar batteries?

This will entirely depend on what level of storage you want and how often you are likely to use the battery for stored energy. More and more companies are entering the market and creating a wide range of sizes, from 1kWh (kilowatt-hour) to 14kWh. The bigger the battery, the more you can store.

A kilowatt-hour is the standard unit used by all energy companies to measure your use and refers to 1000 Watts of power used per hour. The average home, depending on size and occupants, will use between 2000 kWh and 4,500 kWh of electricity per year. One kWh is roughly the same as watching TV for three hours or boiling a kettle ten times.

A typical solar battery will cost between £2000 and £4000, but most people will pay less than £4000 for a good quality battery. Most batteries come with a 10-year warranty, protecting your investment for a long period of time and guaranteeing you won’t need a new one for a while. Unfortunately, solar batteries do not currently have the same longevity as solar panels, so you are likely to need to replace them at some point, but they are getting better, and more companies are extending the life of their solar batteries. See Tesla Powerwall .FYI – Post coming soon! 

Tesla powerwall


Lead acid batteries can be purchased for a lot cheaper, but they tend to be less efficient and wear out much more quickly. Lithium-Ion batteries are usually the best option for a long-term solution and most manufacturers only make Lithium Ion batteries as they are much longer-lasting.

Some of the more recent developments in solar batteries include linking to smart technologies such as an app or Wi-Fi, which can display a range of information including the charge level of the battery, usage, and savings made.

Anything else I should consider?

Always get three quotes from registered installers and check the warranty and how many charge cycles each battery is guaranteed for. Like any rechargeable battery, the more it is used the less efficient it becomes and having more charge cycles means it will last even longer. Typically, you can expect 5,000 to 10,000 cycles, but some companies are offering an unlimited warranty on charge cycles now.

Solar batteries are not recommended for a D.I.Y. enthusiast to fit themselves and work must be carried out by a registered engineer. Many suppliers will not sell solar batteries to members of the public and will insist on seeing the correct documentation before sale.

Always bear in mind there will be some maintenance costs involved with a solar battery and the engineer can explain how regularly you should have the battery maintained and the expected costs over the lifetime of the battery. These costs will vary by manufacturer and model so be careful not to get caught out with unexpected future costs.

The engineer can advise on the best type of solar battery for your needs, as well as advising on the placement of the battery. They are not small units and you will need to ensure there is enough space to fit them. You will also need to know the type of power (AC or DC) and whether your solar panels allow for a retrofitted battery (most do, but some batteries are specific to certain systems).

Thanks, Rich,

Eon Heat Pumps – Eon is pushing it’s marketing but is the UK ready?

Are heat pumps the way forward for the mass market?

With a noticeable increase in marketing for air and ground source heat pumps from several energy providers in the UK, it is worth discussing whether this could be the right solution to make your home more energy efficient and reduce your impact on the environment. However, first it is worth explaining how this system works before discussing the benefits and points to consider.

Air vs. Ground source heat pumps

Both types of heat pump extract heat from the surrounding environment and deliver this heat into the home. Ground source heat pumps use a loop of pipes, filled with fluid and anti-freeze, under the ground to extract heat from the ground. Whilst the temperature above ground may be below zero, the temperature under the surface is relatively constant throughout the year and as a result, can keep a consistent temperature in your home. If space is limited, a borehole can be drilled to give the maximum surface area for the piping to extract heat from the ground.

Air source heat pumps extract heat from the air and can find heat from the air even when it is minus 15 degrees outside! They work a bit like a fridge, but in reverse. Heat from the air is absorbed at low temperature into a fluid. This fluid then passes through a compressor where its temperature is increased and transfers its higher temperature heat to the heating and hot water circuits of the house.

Heat pumps can keep your home at a constant temperature throughout the year, using a renewable and efficient energy source. You may need to keep radiators on for longer as heat pumps do not heat radiators to the high temperatures a gas boiler might, but because the temperature is constant you would keep your home at a comfortable temperature. You can find more out about at the link: heat pumps 

The benefits of a heat pump 

There are several benefits of moving to heat pumps:

  1.       No need for fuel delivery e.g. coal, oil or a gas supply (if you are in the 13% off grid)
  2.       There are government subsidies available under the Renewable Heat Incentive (RHI)[RM1]
  3.       A reduction in carbon emissions
  4.       Radiators and hot water can be heated, the same as any other boiler
  5.       Minimal maintenance required once installed.
  6.       Lower fuel bills for many people, depending on the existing heating source and efficiency of insulation.

Things to consider

As with any heat source, there are things which must be considered before deciding if a heat pump is right for you:

  1.       Heat pumps need a source of electricity, so you will still have an electricity bill (unless you have solar panels already installed)
  2.       Ground source heat pumps will involve a lot of excavation in your garden to lay the piping initially, but once set up there is very little you need to do.
  3.       Air source heat pumps work best in an open area where there is a good supply of air; even better in a sunny spot in the garden!
  4.       What is the fuel and heating system being replaced? If you have an A-rated condensing boiler you will see minimal (if any) savings in your fuel bills. Heat pumps give the best savings when replacing old, inefficient boilers.
  5.       Do you have enough space? Heat pumps will generally require more space than a modern combi boiler and may involve
  6.       The cost of heat pumps can be high for the initial install. Ground source cost between £10000-£18000 and air source cost £6000-£8000. However, as mentioned previously, there are government subsidies available which need to be applied for separately.

Are heat pumps suitable for the mass market?

In summary, it all depends! Heat pumps are not suitable for small or modern buildings as you will not see the savings in fuel bills and the carbon impact would be minimal due to the electricity required to keep the pump working. Flats will not usually have the outside space for ground source and are unlikely to have enough air flow to make an air source pump effective. The same will be true of most terraced houses as there will be restrictions on space, however this would depend on the size and layout.

air source heat pump

Houses, especially detached and semi-detached, will have the ground space to make a ground source much more viable and the surrounding volume of air for an air source pump to be effective. However, the impact would depend on the level of insulation and what fuel type is being replaced. For the best results, there should be a good level of insulation already installed and of course other energy and carbon reducing measures in place. A heat pump is an excellent investment to reduce bills and your carbon footprint, but only if you are already in the process of improving other aspects of the home. On its own, a heat pump is unlikely to make a huge difference to bills or carbon emissions in the average home. If coupled with solar panels and good quality insulation, heat pumps are an excellent addition to a home striving to be carbon neutral.