Greenhouse Challenge Plus Fact Sheet #8

Hot Water

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. In simple terms-the earth is covered by a blanket of gases called the atmosphere that allows light energy from the sun to reach the earth's surface where it is converted to heat energy. Most of the heat is reradiated towards space but some is trapped by the greenhouse gases in the atmosphere. This is a natural effect, which keeps the earth's temperature at levels necessary to support life.

The problem is that 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.

Greenhouse Challenge Plus

Greenhouse Challenge Plus, launched in 2005, builds on the success of the Greenhouse Challenge to support and encourage industry's management of greenhouse gas emissions. Participating organisations sign agreements with the Australian Government that provide a framework for undertaking emissions inventory reporting, and the development and implementation of action plans to achieve cost effective abatement. Greenhouse Challenge Plus is highly effective in achieving greenhouse gas abatement, and in building
the capacity of both the Government and industry to identify, monitor, manage and report greenhouse gas emissions.

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. To reduce energy consumed by heating water and in turn the resulting greenhouse gases emitted while heating the water, your business will need to use less water, improve the efficiency of your current hot water system or install a more efficient hot water system.

Simple No Cost Changes

Reduce thermostat setting. The temperature on many water heaters is set at an unnecessarily high level. Check that the thermostat is set at a level that is appropriate for the purpose of use of the hot water. 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. For example, you may want to consider setting the hot water system to turn on an hour before your business opens for the day and turn off before close of business.

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. To reduce heat loss in your hot water system, make sure that your hot water storage tank is insulated and sheltered from the weather.
Insulate pipes. Ensure that hot water pipes are insulated. The pipes should have a 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. 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.

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

Install low flow showerheads. Whether you provide showers for staff or as part of your business, changing to low flow showerheads is a simple way to reduce your water bills, energy costs and greenhouse gas emissions.

Investment Projects

Install a solar hot water system. Solar hot water systems are a proven technology that in many cases 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.

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 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 high- temperature 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.

Relocate water heater. Whether you are installing a new system or renovating your premises, consider relocating 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. Long distances between the water heater and the tap often leads to the hot water temperature dropping by the time it reaches the point of use. This means higher temperatures are needed to heat the water and results in energy being wasted heating water that is left to cool in the pipes.

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 water in the system. 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.

Hot Water Fundamentals

To be mailed a copy of this fact sheet or any of our other fact sheets, please call us on 02 6274 1229 or e-mail us on greenhouse.challenge@environment.gov.au


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