How Hot Water Systems Can Be a Great Alternative to Solar Batteries

We all know that solar batteries are expensive, and the return on investment is likely not going to take place inside of the warranty period, which is why many homeowners still don’t have solar batteries. Solar batteries serve as the solar energy storage that you can use during off-peak hours. In short, solar batteries can help power your home throughout the day and night. 

However, did you know that an electric hot water system can be a great alternative? A recent “Active Hot Water Control” project in South Australia can reduce energy demand during peak times for hot water and utilise excess solar exports. As a result, this will help manage grid stability and lower costs. The project’s mission is to conduct trials on household hot water systems aggregated into a VPP, which is remotely integrated with home energy management systems. 

The project will aggregate over 2,400 residential electric hot water systems to act as a big virtual battery. It will help soak up excess rooftop solar power in the form of low-cost electricity and provide an affordable and scalable form of demand management. 

The $9.9 million trial is backed by the South Australian government and the federal government through the Australian Renewable Energy Agency, which will use Rheem Australia’s renewables brand, Solahart. 

The project integrates a Solahart Powerstore with a home energy management system across solar and non-solar households. Those who participate in the trial will be rewarded for such services.

The outcome is still to be seen, yet household hot water systems may change in the future energy plan. 

Hot water systems are important and are one of the most basic energy storage devices available. Before, electric hot water systems were timed to charge at night, but recent observations show that it is better to have them charge in the middle of the day when excess solar energy is being exported to the grid. 

Another economic energy storage for your home

To make the most out of an electric hot water system and your solar PV system, activate your hot water system when the sun is at its peak in the middle of the day. The system will heat water and store it in your tank for later use. So, instead of selling excess solar energy back to the grid, you can use that electricity to heat water, boosting the value of your excess electricity even more. 


Types of hot water systems

There are different types of hot water systems that you can utilise in your home today.

Solar hot water

Solar hot water systems have solar panels or evacuated tubes, plus a storage tank unit installed on the roof or ground level. Much like a solar PV system, solar hot water systems convert energy from the sun into electricity that, in turn, heats your water.

Heat pump

One of the best things about heat pump water heaters is that they don’t consume a lot of energy, yet they are still highly efficient. It uses a refrigeration cycle to extract heat from the air to heat the water. 

To determine your zone, please see our heat pump RECs and rebates page. The Clean energy regulator also maintains a list.

Gas hot water

Gas hot water heaters are often installed outdoors because they have venting requirements. The most common type of gas water heater is a continuous flow. However, we do not recommend a gas water heater because it can really be inefficient, especially in cold climates. 

Electric Storage

Electric storage is used by almost half of Australian households. This is definitely a preferred hot water system as it is the most affordable to buy and install. A solar PV system can power it. 

Rebates for Hot Water Systems

Solar and heat pump hot water systems may be eligible for renewable power incentives through Small-scale Technology Certificates (STCs). Check out our page for Australian state and territory government rebates and assistance. 

If you’re looking to install a heat pump or solar hot water system, complete our quick quiz and we’ll get you in contact with local solar installers installer in Melbourne who will provide you a FREE solar quote.

Get a quick solar quote, or contact us today toll free on 1800 EMATTERS or email our friendly team for expert, obligation-free advice!

Other Energy Matters news services: