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Key departmental publications, e.g. annual reports, budget papers and program guidelines are available in our online archive.

Much of the material listed on these archived web pages has been superseded, or served a particular purpose at a particular time. It may contain references to activities or policies that have no current application. Many archived documents may link to web pages that have moved or no longer exist, or may refer to other documents that are no longer available.

Hot Water

For Small and Medium Enterprises (SMEs)

Cartoon Image - Greenhouse Challenge Plus Fact Sheet 8 - Hot Water

Climate Change

Climate change caused by greenhouse gases is one of the most serious challenges facing our community. Human actions–particularly burning fossil fuels (coal, oil and natural gas) and land clearing–are generating more greenhouse gases. These additional greenhouse gases trap more heat and raise the earth’s surface temperature. This is called the enhanced greenhouse effect–it causes global warming and is changing our climate.

The impacts of climate change will have social, environmental and economic consequences that will affect all communities across the globe.

Why Small and Medium Enterprises

Greenhouse gas abatement is not just for the big end of town. Climate change will affect all of us and therefore it is to everyone’s benefit to reduce greenhouse gas emissions. Most measures to reduce energy consumption and greenhouse gas emissions will save you money in the long term, increasing profitability. Some measures will even help to improve productivity and the marketability of your business. Reducing greenhouse gas emissions should be seen as an opportunity to provide your business with a strong business advantage.

Hot Water

The range of uses for hot water in small and medium sized enterprises can vary. There are many low cost changes which businesses can make to reduce energy they consume to heat water. This can also result in helping you use less water.

Simple No Cost Changes

Reduce thermostat setting. Check that the thermostat is set at a level that is appropriate for the purpose of use of the hot water as often the temperature on many water heaters is set too high. However, always comply with local by-laws and regulations that determine minimum temperatures for hot water systems depending on the end use of the water. For example, for staff domestic use of water, always ensure that the temperature gauge on storage hot water systems is set at 60°C. A higher temperature than this means that energy is used unnecessarily and a lower temperature than this may allow harmful bacteria to thrive. Instantaneous hot water systems should be set to no more than 50°C.

Turn water heater off. Some businesses do not need to use hot water outside of business hours. By turning off your hot water system at night and on weekends you prevent unnecessary water heating and save money on the associated energy costs. To simplify this process, you can add a timer to electric water heating units to automatically turn the system on and off depending on when hot water is required. Aim to turn on the system an hour before your business opens for the day and turn off before close of business. Boosters on solar systems can also often be turned off throughout the warmer months.

Switch off pumps. If you use a circulating pump, make sure to also turn this off outside of business hours.

Extra water heaters. Some businesses have water heaters that are dedicated to specific tasks. Rather than heating water needlessly these units should only be switched on when needed.

Low Cost Options

Insulate hot water tank and pipes. To reduce heat loss in your hot water system, make sure that your hot water storage tank is insulated and sheltered from the weather. Also ensure that hot water pipes are insulated with an insulating covering at least 10mm thick, with hot pipes enclosed for at least two metres and cold water pipes insulated at least one metre from the water heater.

Install flow restrictors and low flow showerheads. By installing flow restrictors or aerators in taps, or purchasing water efficient taps, you can make significant savings on your water bill as well as save up to 60 per cent on heating costs when compared to using conventional taps. Install low flow showerheads in any showers.

Check for leaks. Even the smallest leak will cost your business money. Ensure the entire hot water system is checked regularly and that leaks and dripping taps are repaired immediately.

Regular maintenance. Hot water systems like all other equipment in your business require regular maintenance to continue operating efficiently. Water heaters with storage tanks should be flushed out annually to remove sediment. Doing this is usually as simple as opening the drain valve at the bottom of the tank and drawing off water until the water runs clear. (See manufacturer’s instructions.) The burners of gas water heaters should be cleaned and tested periodically to make sure that the fuel is being burned as efficiently as possible.

Investment Projects

Install solar pre-heating or hot water systems. Solar preheating panels can be added to many existing systems at relatively low cost and reduce the energy needed by the hot water system. Alternatively solar hot water systems typically will supply most of a building’s hot water needs, or if used in conjunction with a conventional hot water system will reduce the costs for many small businesses with large water-heating needs. Where gas is available, choose gas boosted systems to further reduce greenhouse emissions.

Gas hot water systems. Consider installing gas hot water systems rather than electric systems, as gas systems produce less greenhouse gas emissions (except in Tasmania where electricity is generated from hydro-electric sources) and often are cheaper to operate. Install a 5 star system if possible.

Heat Pump Water HeatersHeat pump systems are much more energy efficient than standard electric hot water systems and may be more convenient to install than solar. If the installation of solar is difficult and gas is not available, heat pumps may offer a good alternative to solar systems.

Install dedicated units. If one part of your business requires the use of significantly higher temperature water than other parts of your business, it may be more efficient to install separate heaters for hightemperature and low-temperature areas. This will save your business unnecessary heating costs associated with needlessly heating large quantities of water to higher temperatures than required.

Buy energy efficient water heaters. Replace your old water heater with a new more energy efficient model. Investigate the energy efficiency options available on various heater models before purchasing a new unit.

Choose the right size. When selecting the size of your unit consider the maximum number of hot water outlets likely to be in use simultaneously. This will allow you to choose a capacity that will meet demand without wasting energy heating excessive amounts of water.

location of water heater. Whether you are installing a new system or renovating your premises, aim to locate your water heater as close as possible to the main point of use of the hot water. This will reduce heat loss from pipes by minimising the length of hot water pipes that transport the water from the heater.

Buy water efficient appliances. When purchasing equipment for your business, including appliances such as dishwashers and washing machines, make sure these are water efficient. Educate staff to use the equipment as efficiently as possible.

Additional Benefits

Safety. Staff safety will be increased as reducing the temperature of water heaters is a proven means of reducing the risk of scalding accidents.

Water savings. Many of these suggestions are based around reducing the amount of hot water used. This will not only result in energy savings (due to reduced heating costs) and the associated reduction of greenhouse gas emissions but also produce dollar savings on your water bill.

Case Study

Bostik is an Australian manufacturer of products for construction, packaging, stationery and automotive industries.

Wanting to investigate emission reduction strategies, Bostik focused on the potential reduction of energy consumption by using more efficient heating systems to replace their current boiler.

It was discovered that by replacing a central steam boiler with localised heating systems a potential annual emission reduction of 349 tonnes CO 2-e and savings of $54,600/year could be achieved.

Capital cost of replacing the heating systems are estimated to reach $194,000 with a simple pay back period of 3.6 years, and with an additional saving of 5.1 megalitres of water per annum. 1

Hot Water Fundamentals

1 Emission savings based on research undertaken by the student placement initiative run through North Link/NIETL and RMIT University, in partnership with the Greenhouse Challenge Plus program and are estimates only.

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