If you’re an oil heating customer you don’t have to choose between your dependable oil system and a renewable alternative. Instead, adopt the hybrid approach and enjoy the best of both worlds!
Hybrid systems (sometimes called bivalent systems) combine two or more heating technologies in one combined system. We recommend solar water heating and air source heat pumps as the best renewable technologies to partner with an existing oil heating system. It’s already possible to create a hybrid heating system using off the shelf components, but manufacturers are currently working on more complete solutions and these are likely to be available very soon.
The UK climate allows a solar energy system to use the heat from the sun for a large part of the year. Unfortunately, its performance depends on the season and it can’t generate sufficient water temperature for a typical central heating system (which needs around 80°C).This means solar water heating (sometimes called solar thermal) can’t be used as a stand-alone heating system, although it will provide most of your domestic hot water requirements during the summer. However, even in winter solar energy can be used to raise the temperature of the cold water supplied to a hot water storage cylinder, which means that the main heating system then uses less fuel to raise the temperature of the water to its required level. It is usually quite easy to integrate solar thermal with an existing oil heating system and we recommend you contact a local OFTEC registered installer for advice.
An air source heat pump will need to be attached to an external wall heat pumps produce some noise during use so care must be taken not to disturb neighbours.
There are two common heat pumps for use in domestic property. Air source heat pumps (ASHP) use energy in the outside air to produce hot water for domestic heating and hot water systems. They work a bit like a fridge in reverse. However, they produce heat at relatively low temperatures compared to typical oil heating systems, which is why they are best used to compliment an existing oil boiler, rather than as a replacement.
Used in this way, an ASHP can provide all the heat you need during mild weather, and can be supplemented by the oil boiler when things turn colder. This twin system approach can be very effective at cutting heating costs because the oil boiler and ASHP are being used in the most efficient way possible.
Ground source heat pumps (GSHP) are similar to ASHP but take energy from the ground instead of the air, using a buried ground loop or borehole to transfer heat into a building to provide heating and hot water. These are usually more efficient than an ASHP but are much more expensive to install. They also require more space. For most homes, an ASHP is a better option as a compliment to an existing oil heating system.
It is also possible to combine all three systems together – oil, solar water heating and an ASHP. This is potentially the most efficient and environmentally-friendly system of all, and will have the biggest impact on reducing your carbon emissions.
An air source heat pump will need to be attached to an external wall Heat pumps produce some noise during use so care must be taken not to disturb neighbours Planning permission may be required
If you’re struggling to afford your energy bills, you might be able to take advantage of certain benefits, grants and help offered by the government and energy suppliers.Contact Citizens Advice For More Information
Combining your oil heating system with a renewable technology will significantly reduce your household’s carbon emissions. Assuming a household energy requirement for heating of 23,000 kilowatts per annum, a home with a condensing oil boiler running for 90 days and an air source heat pump, with a seasonal performance factor (SPF) of 2.5, running for 275 days, we calculate that the CO2 emissions would be 5,138. This is a 19% reduction compared to using a condensing oil boiler as the only heating source. An air source heat pump with a higher seasonal performance factor would result in even greater savings.
At present we don’t recommend any renewable energy systems as a complete replacement for oil heating in most homes, unless major household renovation work is being considered. This is because many of the most popular renewable technologies produce heat at much lower temperatures than a typical oil boiler which supplies hot water at around 80°C to radiators, and 60°C for domestic hot water.
Older properties are unlikely to have sufficient thermal efficiency for low temperature renewable heating to work successfully as a straight replacement for an existing oil heating system. Significant home renovation is usually needed to achieve comfortable room temperatures and reliable year-round performance. This could include substantially improved insulation, double glazing, improved heating controls, more or larger radiators and under floor heating – all of which can add to the cost of the installation and will cause significant disruption. For many period homes, this level of modification may simply not be practical. In newly-built homes, which can be designed with low temperature heating mind, these issues are less of a problem as the solutions can be built in as part of the design.