While propane is most commonly used for domestic, commercial and industrial heating applications, a shift is now on that could see this Liquefied Petroleum Gas, or LPG, play a bigger role in reducing the energy consumption of buildings.
Propane certainly has a lot of things going for it, especially in remote rural and outback locations unable to be connected to the main electricity grid.
It boasts strong environmental credentials. According to the BRE in the UK, LPG is the lowest carbon-intensive fuel available in gas-main-free areas.
Furthermore, a recent study by energy consultant NIFES Consulting Group commissioned by Calor Gas showed that commercial buildings can reduce carbon emissions by 22 per cent by replacing an old oil boiler with one that uses LPG. This was partly a result of a more efficient system, and partly a result of the emissions factor for fuel oil standing at 0.265 kilograms of CO2 per kWh, higher than that of LPG, which comes in at 0.214 kilograms of CO2 per kWh.
In addition, a separate study published earlier this year in the peer-reviewed journal Environmental Impact Assessment Review earlier proved that, in domestic buildings, heating oil generates about 20 per cent more greenhouse gas emissions than LPG.
It is also more energy efficient. The same NIFES study also showed that an oil boiler installed 15 years ago replaced with LPG can cut energy use by 11 per cent.
From a supply and performance perspective, LPG has also been demonstrated to be more reliable. One volume of liquid LPG will yield about 270 volumes of vapour. This enables high volumes to be stored on-site as liquid in pressurised containers. Also, because LPG is stored under pressure, it is difficult to illegally siphon off – a growing problem for oil storage tanks.
It boils at -42ºC at atmospheric pressure, which means that its performance is not affected by cold weather. This means it can provide a constant supply of gas throughout the year whatever the temperature.
Though highly flammable, it still has good safety credentials, at least from a pollution perspective.
Safety LPG is non-toxic and a leak of LPG vapour is unlikely to pose any significant ground or water pollution hazard. As a liquid, it is lighter than water so has the environmental benefit of always remaining above the water level. Any LPG spillages simply vaporise and do not cause soil or water contamination.
Furthermore, LPG suppliers typically own and are therefore responsible for the upkeep and maintenance of the LPG tank installation. This means each time a delivery is made, the tank is checked by the driver and, periodically, the installation is checked by a qualified engineer. Essentially, this means that the tanks are one less thing for the home or business to worry about.
LPG can be integrated with low-carbon and renewable technologies to provide solutions for rural commercial developments and refurbishments, which combine to create a reliable year-round heating supply with further carbon and cost savings; an increasingly attractive option, especially given the potential effects of the Carbon Tax.
Renewable and low-carbon technologies that can be used with LPG include condensing boilers, solar and photovoltaic installations, gas absorption heat pumps (GAHP) and combined heat and power systems (CHP).
A modern condensing LPG boiler will lower fuel consumption as much as 30 per cent by reusing the energy that would typically be lost through the flue. Condensing LPG boilers are suitable for most commercial premises.
The lower greenhouse gas emissions produced by using LPG compared to oil make a condensing LPG boiler particularly suitable as a year-round back-up to solar power.
GAHPs are low-carbon solutions for heating and hot water which can use LPG as a clean primary fuel source. They are suitable for outdoor operation, which means there is no need for a plant room, and can achieve extremely high levels of efficiency.
A CHP system is effectively an on-site, stand-alone power plant, which is capable of producing both electricity and heat from a single fuel source. While the generator produces electricity, the heat by-product is captured and used for central heating and hot water. If additional heat is required, a back-up condensing LPG boiler can boost output.
With demand increasing for high-performing energy solutions, the rise of LPG is certainly making a good case as an alternative. For remote locations, it may well be the best solution.