In this post, we’ll look at the four most common renewable energy technologies and assess which would be best for your home.
It’s 2019, the world continues to push the boundaries of technology. Solar panels? Now a very normal sight; saving homeowners vast sums of money, contributing to a cleaner and greener environment and aiding the transition from fossil fuel to clean energy, with the ultimate goal to stop our only world getting too hot.
But is it worth it? Let’s do a brief overview of the four main domestic renewable technologies and find out…
Solar thermal is the conversion of sunlight to heat a cylinder of hot water. There are two main types of product
1. Evacuated tubes – cylindrical glass tubes that heat a liquid flowing through it
2. Flat plate panels – much like a photovoltaic panel in appearance, they have multiple tubes running through their core absorbing the solar irradiation.
Popular on the continent and especially along the coast of the Mediterranean, Solar Thermal is ideal for a hot climate. Here, heating isn’t required for a lot of the year so the system commonly just provides hot water for homeowners to use for cleaning and showering/bathing, whilst occasionally providing supplementary heat for a swimming pool.
Solar Thermal is a time-tested technology and is an important part of the renewable energy mix.
The average cost of a Solar Thermal system to a homeowner is around £4,500. The savings obviously vary, as they do with all renewable energy technologies, but it’s assumed that as an average over the course of a year, a homeowner spends around £600 on gas to heat their home and only around 30% of that gas is expected to heat hot water. So, by that rational, a solar thermal system has the potential to save you up to a 70% portion of a maximum of the £180/yr you spend on heating hot water; therefore, an average homeowner could expect to save a maximum of £126/yr.
Does Solar Thermal need maintenance? Yes. It is advised to have your system serviced annually to ensure antifreeze and fluid levels, components like pumps, cylinders and other moving parts are as they should be.
So, in summary, if we assume that a service of a Solar Thermal system costs around £75, this therefore leaves the homeowner with just a £51/yr annual saving.
Air Source Heat Pump
Air source heating is set to become the most common and most efficient way to heat a home. Government has banned all new gas installations into new-build homes from 2025, and - pardon the pun – the Air Source market is now really heating up. Costs are reducing, however slowly, and the market continues to grow from strength to strength. But what is it?
An Air Source Heat Pump is basically a reverse-fridge. It uses ambient outside air temperature to warm up a refrigerant liquid inside it and transfers that heat differential into hot water and home heating.
This renewable energy technology continues to get more efficient and is a great way for new-build properties to stay warm.
However, it does have drawbacks. Air source heating creates heat at a significantly lower temperature to that of a traditional gas boiler, meaning the heat is most efficiently applied in a different way, normally through underfloor heating. When retrofitting an air source heat pump, its most common to have to increase the size of the emitter – in most cases a radiator – by up to at least twice its current physical capacity. Not only is this not always achievable, it significantly increases the initial outlay of a system as a full set of radiators for a typical house can cost upwards of £1,000. This can, more often than not, also mean a homeowner has to have substantial remedial works done to the property.
A typical Air Source Heating installation retails around the £6,000-£10,000, so also represents a more-than significant outlay. Servicing of the equipment is essential and any warranty with a manufacturer will be void if the service schedule is not upkept by a professional.
The amount of money an Air Source Heat Pump can save varies significantly according to your current source of heating. For example, a homeowner who currently uses oil, will save proportionally more than a homeowner whom currently has a gas connection.
There are incentives available to install heat pumps, though this must be balanced against an anticipated increase in electricity usage, as all Air Source Heat Pumps run exclusively on electricity. It would be a sensible addition to fit a Solar PV system alongside an Air Source Heat Pump to combat that increased demand.
Briefly heralded as the next big thing, Biomass heating has more than bumbled its way around the renewable energy market in recent years. This technology has been held back in the domestic market by its bulk, impracticalities, maintenance and general application. However, it is flourishing in a commercial market where large amounts of heat are required.
Biomass heating is the process of burning wood pellets or logs to create heat and hot water. It is efficient and kinder on the environment than traditional heating, though can be costly to install.
Although biomass qualifies as an RHI eligible product, it is generally only considered feasible for larger or off-grid gas properties. The RHI incentives are good and a homeowner can get a significant return on investment, though maintenance and application prevent it from becoming a mainstay technology capable of replacing gas boilers or competing with Air Source Heat Pumps as a mainstream solution.
Solar PV, the most heavily implemented of all mainstream renewable energy technologies continues to go from strength to strength. It now holds its own in a market driven not by subsidy, but purely by savings alone.
Massive improvements in manufacturing and huge growth have reduced costs to the extent that it is now cheaper to generate your own energy than import it from the grid.
Of course, it requires a somewhat significant outlay for a homeowner, though the return on investment and subsequent savings well out-weigh the above technologies. Couple the savings with the convenience Solar brings with its long warranties, vastly reduced maintenance requirement and a minimum lifespan of 25 years, it presents a solid investment in your property.
Solar PV generates electricity. In its purest form, electricity - unlike the aforementioned three renewable energy technologies above – doesn’t limit you to supplementing just heat or hot water, it can manage lighting as well. You can do anything with it, within reason, and generating your own promises your financial security against an increasingly electrified future.
With the continued rapid growth of electric vehicles, the banning of grid gas from 2025 and the onset of more very expensive nuclear power, the cost of electricity is only set to become much more expensive. As technology continues to improve, it will come as no surprise to learn that Great Britain is being geared up for an electrified future.
Battery technology now allows a Solar PV owner to charge their excess generated electricity into a battery, to run their home at night. Even on a very wet or rainy day, flexible energy tariff’s allow them to charge their battery using a cheap rate, whilst discharging during the daytime and evening when electricity is more expensive.
In summary, there is a place in the market for each of the aforementioned technologies, but the most scalable, flexible and promising of them is without doubt Solar PV.
If you’re interested in engaging with renewable technology, use our handy guide below to help you make an informed decision.
If you want to know more, contact us and we can help you.