By 2025, you won’t be able to hook up your house or building to the natural gas network, if the Government follows draft advice from the Climate Change Commission. Despite being just one of more than 100 recommendations, it caught a lot of attention. Mike Hosking called it “stupid”. Chef Martin Bosley​ said it would open “the most unbelievable can of worms” for cafes and restaurants.

The commission’s draft advice will be finalised in May, then the Government must decide whether it wants to adopt it.

According to the commission, the policy will protect the wallets of homeowners and businesses, because the cost of gas is going to shoot up over the coming decades (something you may not hear in the sales pitch for a new gas hob).

It says banning new installations would prepare the country to make the switch, so no one has to choose between years of high bills or replacing a perfectly functional gas appliance.

But would that spell the end of infinity hot showers or the humble Kiwi BBQ? Stuff took a look at the implications.

I already have gas. Is the government going to cut me off in 2025?

No, the proposed ban only covers new connections to the gas network. If you’re already connected, your gas will continue to flow. However, if one of your gas appliances conks out after this point, you could notice a difference. The commission wants the government to tweak the market so zero-carbon appliances become the go-to, says principal analyst Antonia Burbidge​.

“In most cases, we know that electricity is a good option and that pretty much everyone is connected to the electricity network and that it can do the same tasks that the gas is doing,” she says.

I use bottled gas to power my BBQ and gas canisters to cook on tramping trips. Will these be affected?

No, you’ll still be able to swap out an empty gas bottle at a petrol station or hardware store and buy pre-filled canisters. These are typically butane or propane, or a mix of both (LPG). The commission says this is a minor source of emissions, and there aren’t green alternatives yet – but the hope is the industry would see these moves as a signal to start investing in green gas (such as that made from rotting organic waste).

However, the large LPG bottles that are connected to your home, where gas flows through pipes before reaching your appliances, are subject to the proposal. If you want these, you’d need to install a system before 2025.

What about my infinity hot water system? I can’t live without it.

Burbidge says she has a lot of sympathy for people who rely on infinity water heating systems. These are typically gas fired, though electric options exist.

The proposal won’t require anyone to uninstall their current working system – and when the kit comes up for replacement, the commission is calling for the electric alternatives to be freely available and affordable for consumers, so no one is forced to buy inferior technology.

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“The complaint I’m getting from everyone – that you’re taking away our good hot showers – is not quite true any more. The electric options are just as good.”

However, Master Plumbers, Gasfitters & Drainlayers chief executive Greg Wallace​ stresses going electric won’t work in every situation.

The commission wants the gas connection ban to have an exception – if the person or organisation can demonstrate that the low-carbon fuels aren’t a viable option.

Wallace also worries about a consumer energy market completely dominated by electricity. “I honestly believe having alternative energy sources protects consumers, maintaining a competitive environment.”

This has come out of nowhere. Can’t they give everyone more time to prepare?

Wallace says the draft proposal was a big shock for the gasfitting industry. “There’s a lot of anger about the way this was released.”

In its draft report, the commission said financial support must be directed to the workers, such as gasfitters, that will be affected by its proposals. Wallace also backed the idea.

“To be blunt, you’re destroying their business. It will gradually reduce to a point where it will be unsustainable,” he says. “Our businesses are down by 25 per cent now. There're no subsidies being offered now. These are mum-and-dad businesses.”

Government inaction until this point has left the industry high and dry, he says. “We could have retrained a lot of our gasfitters into solar installations and all sorts of things – but we’ve stood back, and then all of a sudden, we seem to be picking on a very small sector.”

The commission is up against a hard deadline, set by the Zero Carbon Act: we must be carbon-neutral by 2050.

An infinity hot water system could last 20 years before it dies, so gas appliances installed in 2024 may not be replaced until 2044, six years before we must be carbon-neutral. A ban in 2025 means most appliances will be able to live out their full life, potentiality sparing homeowners additional bills.

Natural gas isn’t a bad fossil fuel – right?

Understandably, the “natural” in natural gas makes this fuel sound more environmentally friendly than it really is. However, it’s methane, a very potent greenhouse gas. When you burn it in your gas hob or cylinder, you release carbon dioxide.

Natural gas appliances also release toxins, such as carbon monoxide and nitrogen dioxide, which can harm your health from the combusted gas.

There are also issues with how we extract and transport natural gas – some escapes, causing atmospheric damage. And although it doesn’t last as long in the air as carbon dioxide, methane is 84 times more potent in the first 20 years of its life.

LPG is another source of carbon.

There’s an urban legend that natural gas is more efficient – and therefore produces fewer emissions – than electricity. There’s an illusion of truth here: If your traditional electric cylinder is heated using electricity entirely generated by burning coal, it will generate more greenhouse gas than a natural gas-powered model.

However, less than five per cent of the country’s power each year is generated from coal, though this is unevenly spread – more coal is burned during winter, when we’re jumping in a hot shower and switching on heaters.

But even in the wintery days of last July, coal-fired power reached no more than 8 per cent during peak times, according to Transpower.

In a 2013 report, the Energy Efficiency and Conservation Authority found that a unit of electricity has half the carbon footprint of gas, even though 20 per cent of electricity comes from burning fossil fuels (including gas). And many new appliances, such as heat pumps and induction cooktops, are more efficient at turning fuel into heat, so these offer better bang for buck than gas.

Burbidge says our electrical grid is already one of the greenest in the world. “It is only going to get more clean. The more we can use that low-emissions electricity system to displace emissions elsewhere in the economy, the better. Increasing demand will push the build of more renewables – more wind and more solar.”

How much gas do homeowners burn?

Residential homes consumed about 3 per cent of the country’s natural gas in 2019. Commercial buildings, which will also be subject to the ban, burn another 5 per cent for activities such as space heating, hot water heating and cooking.

That doesn’t mean we’ll reduce demand by 8 per cent, though, because the ban only covers new connections.

However, homes and buildings switching away from natural gas could free up the supply for electricity generation. Companies using a large proportion of our annual gas supply are also projected to move operations overseas, freeing up more.

For the next 15 years at least, the commission sees natural gas as an important back-up fuel to create electricity during dry and still spells, when hydro lakes fall and wind turbines slow. It’s a less polluting option for this purpose than burning coal.

Will this proposal cause my energy bills to rise?

Critics of the proposal say natural gas is cheaper than electricity, with a single unit (a kilowatt-hour) of gas costing about half that of electricity.

But that’s an apples-to-oranges comparison, because different appliances can require more energy to do the same job. Modern electrical appliances – such as the heat-pump tech that warm rooms and water – can be far more efficient. So even with the higher unit price of electricity, they can be cheaper to run.

Besides, gas isn’t going to stay cheap forever. The cost to burn fossil fuels will rise significantly in the coming decades, so the average household using gas could pay an additional $150 each year in energy bills by 2035. If large users of natural gas significantly cut back due to higher costs, this could lead to big swings in the price. The cost of maintaining or upgrading the underground piped network could also fall on smaller and smaller numbers of customers.

What about “green” gas?

We can make zero-carbon gases, including one known as biomethane. This is the same chemical as natural gas, but since it comes from organic material rather than from underground, it isn’t adding additional carbon to the atmosphere (though we’d need to minimise leakage).

We currently capture some biomethane from landfills, where our organic rubbish breaks down. It’s currently burned, with the heat used to create electricity. Although that’s better than wasting it, the country should put that gas to better use, says Brian Cox​ of the Bioenergy Association.

In future, he envisions the gas being purposefully created from waste, refined, and used in restaurants and factories where electricity isn’t a suitable option. “To me, it’s a no-brainer.”

Since we don’t create enough organic waste to entirely replace all the natural gas we burn today, biomethane could become a premium product.

We can also create and burn low-emissions hydrogen gas, and the country may start to blend this with natural gas. Yet there are some thorny issues. Hydrogen is created using electricity – and it’s hard to know whether this will be an affordable option for the energy used in home cooking and heating.

On the one hand, it’s more efficient to use electricity directly, since some energy will be lost in the conversion. On the other, hydrogen could be made overnight when power usage (and the spot price) falls.

But there’s likely to be high demand for hydrogen, as it will also be a low-carbon way to power trucks, buses and even ships.

Finally, hydrogen has some concerning safety issues. If it leaks, hydrogen is more likely to explode than natural gas. A tiny static electrical spark is enough to cause a bang. Putting the gas into a piped network, such as the current system, is a risk the country may not be prepared to take.

Although the commission thinks expanding the natural gas network isn’t compatible with our target to be carbon-neutral by 2050, the future of zero-carbon gases and the gas infrastructure network is an open question, Burbidge says. “Everyone needs to be part of that conversation.”

What else could we do, other than a ban?

A ban isn’t the only tool for the government to get people to switch away from natural gas. Instead, it could make fossil fuels increasingly expensive – which is what our Emissions Trading Scheme (ETS) is designed to do. It’s projected to add $12.50 per month onto the average gas bill by 2035, under the commission’s roadmap.

There are calls for the ETS to be left to go it alone, without additional regulations such as the ban.

But the scheme has some holes. As gas prices rise, homeowners are likely to switch away, but that may cause the price of gas appliances to drop. Landlords could take advantage of these cheaper appliance prices, since they won’t be the ones footing the eventual energy bills.