Which is better: heat pump or solar hot water?
Heating the water for your home can account for, on average, a quarter of the energy you use! So, if you’re looking to reduce your bills by installing a new hot water system, which is the better between a heat pump hot water system and a solar hot water heater?
Heat pump water heaters and solar hot water heaters are both types of renewable hot water systems. Both will give you the hot water that your household needs, and energy savings to boot but the initial installation costs and other factors do need to be considered.
Hot water heat pumps
Heat pump hot water systems actually work similarly to a fridge, but in reverse. Heat pumps absorb the heat from the outside air and transform it into hot water, whereas fridges pump the hot air out into the outside atmosphere. Electricity pumps refrigerant through the system then the refrigerant transfers the heat absorbed through the air to the water in the tank.
There are 2 types of heat pump hot water systems:
- Integrated or compact systems
- Split system
Both the integrated and split systems comprise of a compressor and storage, but the difference comes in whether they are kept together or as separate entities. Neither the split nor integrated system is more efficient than the other but the choice between them comes down to how much space you have available. If you have limited space, the split system would probably be your best option as you can have the 2 components in separate locales.
Solar hot water heaters
Solar hot water systems heat your water by utilising the heat directly from the sun via solar collector panels that the water travels through to be heated on its way to the hot water storage tank. As the sun shines on the solar collector, the water in the pipes inside the collector becomes hot and rises up through the pipes and exits the collector to travel to the storage tank.
What are the benefits: heat pump vs solar hot water
Heat pump advantages
- Lower initial cost that a solar hot water system
- Extremely energy efficient as they use up to 4 times the electricity that electric hot water systems use
- More environmentally friendly as heat pump systems collect 3 times the energy that they use
- Can operate without sunlight so can run on off peak electrical rates
- Long lifespan of 20+ years (if well maintained)
Heat pump disadvantages
- Greater up front cost for the system
- Makes a low hum similar to that of an air con unit so it’s important to consider where to install
- Can take more time to heat up in colder conditions
- Servicing can be more pricey than traditional electric or gas hot water systems due to increased frequency required e.g. heat pump: 3 - 5 years, gas/electric: 5 - 8 years recommended
Solar hot water advantages
- Much more efficient (providing collector panels are in correct position)
- Extremely reliable system
- Lower maintenance costs
- Government rebate can off some of the cost
- Long lifespan of 20+ years (if well maintained)
- Do not require mains electricity
Solar hot water disadvantages
- Expensive to purchase and install cost
- Can depend on the weather and sunlight for efficiency
- Requires roof space for the solar collector
- Large buildings and trees nearby can reduce power production
Which is better for you?
If you don’t mind the initial cost of a solar hot water system and installation and want to heat your water supply with free solar energy, then a solar hot water system may be the right choice for you. The savings on your utility bills and the benefits for the environment make solar hot water an impressive proposition for many households. However, this is not as viable if it would be situated in a shaded area as the system would not be as productive.
If the cost of a solar hot water system is deterring you, the heat pump system will be the way to go. The upfront cost of the system and installation can be significantly less and the heat pump system does not have the weather and location constraints of the solar system. When you consider having the heat pump system on a timer, you can have it heating your water during off-peak hours to make the most of cheaper electricity.
Still not sure? Well, there's actually an even better option if you have solar panels as you can run the heat pump system during the day when your solar panel system is generating electricity. Essentially, you have the benefits of both systems in one as you can utilize the free solar power to heat your water and negate the mains electricity usage. Because heat pump systems are so efficient, the electricity generated by your solar panels will still be capable of running your household appliances simultaneously.
For honest professional hot water system advice, contact the experts at Pure Plumbing Professionals on 02 8188 5339 or complete our online hot water system enquiry form.
