
21 Nov Is investing in energy efficiency a good idea?
By James Sumner, Executive Director, Warfield Park, Bracknell Forest.
This article was published in the November 2023 issue of Park Homes & Holiday Living magazine.
Over the past two years we have all seen our energy costs rise significantly. The average home energy costs are now over £3,000 per year. Although many of us have taken steps to reduce our energy consumption, what about investing in energy efficiency in our park home to make more significant reductions in energy use in the long term?
The energy crisis was heightened by the Russian invasion of Ukraine. It exposed just how vulnerable the country’s energy supply is both to physical disruption and market forces. The restriction on natural gas from Russia resulted in massive increases in wholesale gas prices, passed on to our energy costs. But even before the war, the world emerging from COVID was seeing increased energy usage which was also pushing up prices.
Investing in energy efficiency in your park home will reduce your energy use and your CO2 emissions from day one, and will in time pay back the capital investment and bring long term savings. So, what investments can you make?
New boiler
Park homes built since 2005 have condensing boilers, as will be any replacement boilers. A condensing boiler is 90-99% efficient compared to the typical 78% (older ones 55-65%) of a non-condensing boiler. This would save around 1,200kg of carbon a year (figures from www.greenmatch.co.uk) and, according to the Energy Saving Trust, saving you £310 per year.
When considering a new boiler, you can choose between a ‘system’, which has a separate hot water tank, or a ‘combi-boiler’ which produces instantaneous hot water. The choice will depend upon a number of factors. System boilers tend to be more efficient, but combi-boilers require less space, which is a major consideration in a park home. But with energy efficiency in mind, system boilers with the hot water tank are compatible if you also wish to have solar water heating, and is also ‘heat pump ready’ – in the coming years replacement gas boilers will be phased out and you will have to install a heat pump. Of course, you could simply opt to install a heat pump now (see later).
Additional insultation
Modern park homes come with significant inbuilt insultation to conform to British Standard BS3632. This provides energy efficiency which is better than the majority of the current housing stock in the UK. There is also the option, if you are buying your park home from the manufacturer, to specify higher insultation.
For an existing park home, especially ones built before 2016, check the current insultation and consult an expert insultation company to find out whether further insulation would be beneficial. Consider the capital cost of new insulation compared to the energy saving it would achieve – this will determine the ‘pay-back period’ and whether it is worth the investment.
There are several types of insultation:
- Wall insulation is external cladding consisting of insulating panels affixed to the outside of your park home and then rendered or clad to a desired finish. It may require your windows to be re-aligned, which also offers the opportunity to relace them if they are not energy efficient. Wall insulation also helps keep your park home cooler in the summer and increases sound insulation.
- Roof insulation involves installing additional insulating materials in the loft space.
- Floor insulation takes the form of foil-clad thermal panels affixed to the underside of your park home, or spray insultation on the underside. The latter can cover pipes and wires, if not done correctly, making them difficult to access in future.
Figures from the Energy Saving Trust say that the costs for insulating a park home can range from £8,000 to £20,000, depending upon requirements. Savings could be on average be £455 per year in energy costs.
Solar power
Solar power comes in two forms: solar water heating and solar photovoltaics (PV). Both involve installing panels on your roof.
Solar water heating utilises the heat of the sun, via solar collectors on your roof, to heat water in your hot water tank. The system works all year round providing around 90% of your hot water during the summer months, dropping to around 25% in the winter. So, further heating via a boiler or immersion heater will also be required to make up the difference. The cost of a solar heating system is between £3,000 and £5,000. It will save around half the cost of heating your hot water on average – more in the summer, less in the winter.
Solar PV generates electricity from light via panels on your roof which you can use in your home, charge batteries or export to the grid. Based on a typical household with a 3.5Kw system, the Energy Saving Trust estimates you could save between £175 and £420 per year at the current Domestic Price Cap rates if you use the electricity yourself. When compared to a typical cost of £7,000 would mean a pay back period of between 14 and 22 years (Energy Saving Trust). If you export the electricity to the grid the Energy Savings Trust estimates you could earn between £100 and £145 per year (based on 5.5p per KWH, but different suppliers pay different rates across the county under the Smart Export Guarantee (SEG) ranging from 3p to 16.5p). Although it will be profitable for many, you need to do the calculations.
Where electricity is supplied via the park operator’s electricity network, exporting electricity to the grid may not be possible although it will still offset your overall electricity consumption and save you money, depending on the KWH charged.
Note that permitted development (PD) rights are often restricted on park home sites so you may need planning consent to install panels on your roof – you should check with your local council. You may also have to ask the park operator for permission.
Battery storage
Battery storage is an emerging technology, driven by its use in the automotive industry.
The problem with solar PV is that most electricity is generated during the day when it is least needed. The highest demand is in the early evening. Batteries enable the electricity generated in the day to be stored and then used when it is required.
Battery storage often comes with solar PV installations, adding around £4,500. This will add time to your pay-back point – Solar Energy UK says it can add an extra five to 13 years.
Heat pumps
Heat pumps are the current favourite technology to take over from gas and oil heating systems. After 2025, new homes will have heat pumps for their heating and hot water, and ultimately renewing boilers will require you to switch away from fossil fuels.
Heat pumps can be best described as air conditioning units in reverse: they take energy out of the air (or the ground) and use it to heat your home. They are a highly efficient system – for every kwh of electricity used 3kw of heat is produced and so a 7kw heat pump outputs the same amount of heat as a 21kw boiler. But the capital outlay is high: installations costing up to £14,000, although there are various grant schemes available.
The savings when switching from older electric storage heaters or older oil, LPG and natural gas boilers can be dramatic – the Energy saving Trust estimates savings at £1,100, £455 and £460 for electric, oil and LPG respectively, leading to pay-back periods of 13, 31 and 30 years respectively. Savings for newer electric, gas, oil and LPG boilers would only result in very modest savings.
In terms of carbon savings compared to older systems, a heat pump will save 2,900 kg/year replacing an old gas boiler, 2,000 kg/year for old electric storage heaters, 4,400kg for an old oil boiler and 3,400kg for an old LPG boiler.
Two objectives
There are two objectives here: to reduce energy costs to save you money in the current cost of living crisis, and to reduce carbon outputs to help address the climate crisis and global warming. Making generalisations, as each park home is different, replacing older electric storage heaters, gas, oil or LPG systems with new gas boilers or heat pumps will have a reasonable payback period and will save you money in the medium term. It will also save significant CO2 emissions from day one.
If your insulation is below current standards, further insulation will save you money and cardon emissions.
Solar water heating and PV will depend upon a large number of factors but in a typical application could save you money in the medium term, and CO2 emissions from day one.
All of the above might also have the side benefit of increasing the value of your home as being seen to be climate conscious and minimising your environmental impact is set to be increasingly important.
As always, the devil is in the detail: you will need to have an expert installer with the required accreditation to come and assess your situation and advise you on the best solution for your park home.
For further information on saving energy, visit the Energy Saving Trust website (www.energysavingtrust.org.uk/).