Heat Pumps

Heat Pumps

Alliance, one of many manufacturers of heat pumps today, introduced a new and efficient way of heating water for both residential and commercial applications, to South Africa. A heat pump serves the same function as a geyser, but without the extreme consumption of electricity. Alliance heat pumps display a new and unique form of technology, and are becoming more and more popular (Alliance, n.d.).

Company Logo

What is a Heat Pump? (Alliance, n.d.)

A heat pump is literally a pump that pumps heat. It is basically an air conditioner that operates in reverse. It extracts the heat from inside a building, and uses it to heat the water within a geyser.

Alliance Heat Pump

Common Water Geyser

How does a Heat Pump work? (Alliance, n.d.)

Heat Pumps use electricity to the power a compressor and a fan. The compressor compresses gas into a liquid, which causes it to heat up. This heat is then transferred into a where circulating water is stored. The gas then evaporates, resulting in it cooling down. A fan then blows air over the cold gas-filled piping, which then extracts ‘free’ heat from the ambient temperature which then causes the gas to heat up again. The gas is then compressed again, releasing the extracted heat to warm water and the cycle continues as before. The result of this cycle is: energy-efficient water heating at a third of the cost of electric-element heating.

How the heat pump works

What are the advantages of a Heat Pump? (Alliance, n.d.)

Heat Pumps are very energy efficient; they are easy to work with and to install and are well suited for both domestic and commercial applications. The table below simply emphasizes the efficiency of Alliance Heat Pumps, by comparing them with other types of water heating. This table can be used to compare all heat pumps to other types of water heating.

Table comparing the different types of water heating systems

Heat Pump - one unit of electrical energy produces between 2.5 and 3.5 units of heat energy.

How ambient temperature affects Heat Pump performance (Alliance, n.d.)

The COP, Co-efficient of Performance, of a Heat Pump is the ratio of the change in heat ‘output’ side relative to the supplied work. It is both a measure of the efficiency of a Heat Pump and the conditions under which it is operating. The COP will therefore increase, as the ambient temperature increases. A Heat Pump can work efficiently in areas where ambient temperatures seldom fall below zero. However, in some areas, the use of a Heat Pump in place of other types of water heating may not be very efficient and/or user friendly.

Graph and table showing the effects of ambient temperatures on the performance of heat pumps

The Pros and Cons of Heat Pumps (Absolute Energy Solutions, n.d.)

Heat pumps clearly have many pros, as mentioned before, however like every product ever invented, Heat Pumps also have cons. The table below displays the pros and cons of all Heat Pumps, including the ones manufactured by Alliance. 

Pros	Cons
75% Energy Savings Achievable	Operational noise
Well established technology	Higher initial capital outlay compared to other water heating systems
Simple installation	Needs well ventilated area
Low maintenance required	Operation in extremely cold environments (<-10˚C)  problematic
Good return on investment	Calcium build-up in water can lead to extra maintenance
Cold air as a bi-product	Not well known in South Africa just yet
Small installation foot print

Conclusion

A Heat Pump is a very efficient and sustainable water heating product that guarantees easy installation (like a normal electric geyser), low electricity usage, low maintenance and a good return on investment. However, a heat pump can be somewhat noisy; it may not be very effective in extremely cold areas and is quite pricey. But these are minor issues which can be overcome. Yes, a heat pump can cost between fifteen and thirty thousand rand (depending on the type and size of the heat pump), but in the long run you are guaranteed to save money with regards to electricity and maintenance costs.

We recommend heat pumps over other types of heating products to those who want to save energy as well as money, in areas where ambient temperatures are not below 0˚C.

By: The Quality Surveyors

D.H. van Rooyen        15106625 (Group Leader)

U.M. Holtzhausen       15124275

J.D. Gold                   15119310

M. Moola                    15191380