Your air conditioner has ten star ratings in the government register. Your hot water system has none, and no heat pump is in there at all

We have written before that heat pump hot water is subsidised by government and covered by no efficiency standard. That piece rested on what the rules say. This one rests on what the register holds, which is a different kind of evidence and, we think, a harder one to argue with. The two agree.

What the register is

Products regulated under the Greenhouse and Energy Minimum Standards, the GEMS scheme, have to be registered before they can be sold. The register lists 24 product types, from air conditioners and fridges to swimming pool pumps, computer monitors and distribution transformers. Each product type has its own record shape, and the shape is the interesting part: a field only exists if the scheme measures that thing.

The four we counted

A note on the counting, because we want it checkable. We counted columns whose name contains star or rating. For air conditioners that is twelve columns, but two of them hold the label images rather than a rating, so the honest number is ten: separate stars for cooling and for heating, under both the 2010 and the 2000 methods, plus zoned figures for cold, mixed and hot climates. Fridges likewise have four such columns, two of which are images, so two real ratings. Water heaters have zero columns of either sort.

What the water heater records do hold

They are not empty. An electric water heater record carries the applied standard, brand, model, capacity, height, width, depth, number of heating elements, expansion valves, feed tanks, hot water fittings, temperature and pressure relief valves, the country, an expiry date and a registration number. It is a thorough record of what the thing is. It contains nothing about how much energy it uses relative to any other one.

The standards named in those records are real and current. Of the 1,486 electric registrations, 949 are registered under the Greenhouse and Energy Minimum Standards (Electric Water Heaters) Determination 2012 and 537 under AS/NZS 4692.2:2005. On the gas side, 649 of 677 are under the Greenhouse and Energy Minimum Standards (Gas water heaters) Determination 2017 and 28 under AS/NZS 4552.2:2010. So electric and gas water heaters do face a minimum standard. What they do not face is a comparison.

The heat pump result, and it is a zero

We searched every field of all 2,163 water heater registrations for the words heat pump. There are none. Not a category with no entries, not entries with blank ratings: the technology the Small-scale Renewable Energy Scheme pays people to install does not appear in the register that governs the products it is replacing.

That is consistent rather than contradictory, and it is worth being clear why. The GEMS determinations above cover electric storage and gas water heaters. A heat pump is neither, so it falls outside them, and nothing else picks it up. The register is not hiding heat pumps. It was never asked to hold them.

Our view, labelled as such. The asymmetry is the thing worth noticing. The scheme can describe an air conditioner's heating efficiency in three climate zones under two methods, which is a serious piece of measurement. Applied to the appliance that uses about a quarter of a home's energy, and that governments are actively paying households to change, it currently says nothing at all. We are not claiming a heat pump is inefficient, and the good ones are not. We are saying that if you want to compare two of them before spending several thousand dollars, the national register that exists to let you compare appliances cannot help you, and it will not tell you that itself.

You can check every number above yourself

This is the part we would most like readers to take away, because the register is more usable than it looks. Each product type has a search page, and each search page has a CSV export. Add ?export_format=csv to the search URL and you get the whole set as a spreadsheet: 488 KB for electric water heaters, about 6 MB for air conditioners. No login, no browser tricks, no scraping. The addresses are in the sources below.