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Spa pools, outages and the honest energy picture

A spa that loses power in a frosty outage can cool down, and in hard frosts the pipes and pumps are at risk. Here is what a home hydrogen system is designed to do about that.

The real risk is the cold

A spa pool is an insulated tub of water with a heater, circulation pump and jets. In a summer outage, a cooler spa is just an inconvenience. In an inland winter with hard frosts, a spa that sits without circulation or heat for days can cool right down, and exposed plumbing and equipment can be at risk. Many spas have a freeze protection mode, but it needs power to work.

What it would keep running

Spa controller and circulation pump
Freeze protection mode
Spa heater at reduced temperature
House heating and kitchen

Protecting the tub, not heating for fun

The battery and inverter run in UPS mode, so the spa's controller and circulation pump keep running and freeze protection stays active. That is a modest draw. Heating a full spa back to soaking temperature is not, and during a long outage it would use a lot of stored hydrogen that the house may need. The sensible approach is to let the spa hold a lower temperature until the grid returns. Round-trip efficiency is 30% or less, so day-to-day spa heating belongs on the grid, ideally off-peak.

How it works →

The H2OME loop: an electrolyser splits water into hydrogen, the hydrogen is stored in a tank for weeks, a fuel cell turns it into electricity for your home, and the water returns to the loop.

Fitting it with the house

Spa heaters and jet pumps alongside a heat pump, oven and dryer can approach 15 kW continuous. Most households can manage that by not running everything at once. A large swim spa with big heaters is another matter and may need a bigger setup, sized honestly in the pilot. The system charges on cheap off-peak power or from wind or micro-hydro, and its own water loop is separate from the spa.

Questions

Will it keep my spa from freezing?

It is designed to keep the controller and circulation pump running through an outage, so freeze protection stays active. Check your spa's own manual for how its freeze mode works.

Can I keep the spa hot all through an outage?

Possibly, but it uses a lot of stored energy. With round-trip efficiency of 30% or less, it is usually better to let the spa hold a lower temperature and save hydrogen for the house.

What about a swim spa?

Larger swim spas with big heaters can push past what fits comfortably alongside a house at 15 kW continuous. That would need sizing in the pilot and may need a bigger setup.

Elsewhere

Every use →

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