Often yes if you already have rooftop solar, you still run an electric storage cylinder, and a lot of daytime generation goes out to the grid at a low feed-in rate. A Catch Power solar relay (diverter) can push surplus into the tank you already own — without buying a lithium battery or swapping to a heat-pump hot water system.
It is not always the right path. Tiny arrays or households that already soak most daytime solar are poor fits. If you are on gas hot water, we do not install Catch/diverters on gas — the usual path is to uninstall gas and replace with a heat-pump hot water system. We will not invent kWh or dollar savings on this page.
When a diverter fits
A diverter tends to make sense when:
- You have an electric storage cylinder (we do not fit diverters to gas hot water)
- Your inverter or meter shows regular daytime export
- You still heat water with a resistance element on grid rates at night or in the evening
- You are not ready for a battery, or your evening load does not justify one yet
- The cylinder still has life left — you want to keep it, not replace it
If the tank is failing, compare a heat-pump swap first: Should you replace your hot water cylinder with a heat pump in Hobart?.
Catch Power solar relay in plain English
We quote and install Catch Power solar relays. The relay watches export (or generation) and switches power to the hot-water element when there is surplus. Hot water becomes a “thermal battery” for daytime solar. You keep the electric cylinder. You do not store electricity for later lights and cooking the way a lithium battery does.
Product sheets live on our data sheets page. Specs belong in the datasheet and the quote — not as marketing claims here.
Diverter vs battery vs heat-pump HWS vs do nothing
| Path | What you keep / change | When it usually wins |
|---|---|---|
| Catch Power solar relay | Keep electric cylinder; add control | Solid daytime export; electric tank OK; not ready for battery or heat-pump swap |
| Battery | Keep or add storage for evening loads + optional backup | Evening imports dominate; backup matters; CHB discount may apply — see Solar batteries Tasmania and Is a home battery worth it? |
| Heat-pump HWS | Replace cylinder with heat pump | Tank failing or inefficient; site suits outdoor unit — Replace cylinder with heat pump · HWS service |
| Do nothing / export | Status quo | Little surplus; FiT acceptable to you; hot water already timed into solar hours |
More on the mix of use, store, and export: Use, store or export.
Tasmania’s regulated feed-in floor is useful compared with many mainland states, but import rates are still usually much higher than feed-in — so self-use often beats chasing export cents alone.
What we check on site
- Cylinder type and element circuit (electric storage only for Catch Power)
- Switchboard space and safe switching of the hot-water circuit
- Solar size, inverter type, and how export is measured
- Whether a simple timer already captures most solar hours (sometimes control is enough without a diverter)
- Whether a battery or heat-pump path would solve a bigger problem than hot water alone
FAQs
Will this work with gas hot water?
No. We do not install Catch Power on gas hot water. If you are on gas, we usually uninstall gas and replace with a heat-pump hot water system.
Does a diverter replace a battery?
No. It stores heat in the tank, not power for evening lights and cooking. Different job.
Do I still need a heat pump later?
Maybe. A diverter keeps a healthy cylinder working harder on solar. A failing tank is still a replace-or-not decision.
Next step
Request an assessment. Bring inverter app screenshots or a recent bill if you can. We will say whether a diverter, battery, heat-pump HWS, or better timing is the honest next step.