Solar and wind could deliver zero carbon gas grid by 2050

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Large-scale solar and wind energy generation will not only be key to decarbonising Australia’s electricity grid, but would also form the foundation of a zero-carbon gas network, a new report has found.

The report, published by Energy Networks Australia on Monday and building on the Gas Vision 2050 report, says that Australia’s current gas network could be decarbonised by 2050, through a combination of renewables generated hydrogen fuel, waste to energy biogas, and carbon capture and storage technology.

In particular, the report talks up the potential of using Australia’s vast solar and wind resource to produce hydrogen fuels, that could be injected into existing gas networks; used for industrial heating, space heating and cooking; and to mop up and store excess renewable energy generation.

ena gas graph1

The findings of the report, based on research by Deloitte Access Economics, paint a markedly different picture to other studies modelling zero emissions grids, where gas is largely phased out in favour of solar, wind and hydro generated electricity, and balanced by energy storage and smart management.

Instead, the ENA claims that the decarbonisation of both the gas and electricity networks together would capitalise on existing infrastructure, bolster the uptake and optimisation of large-scale renewables, and provide the best outcome for consumers in the longer term, in terms of cost.

“The electricity required to replace the energy provided by the gas network will require vast upgrades to electricity generation, transmission and distribution infrastructure as well as additional investment in electricity storage,” the report says.

“This raises important questions about practicality and cost.”

To illustrate this, the report cites the case of Victoria, where the gas network currently provides 69 per cent of household energy a year. Switching from gas to 100 per cent electricity in that state, it says, would result in a doubling or tripling of peak electricity demand in winter.

“Gas distribution networks comprise large, long-lived assets. Repurposing this infrastructure to use decarbonised gas is likely to lower the overall cost of the emissions reduction task,” the report says.

“Our gas infrastructure and networks (also) have the capacity to store unused renewable electricity to manage hourly, daily and seasonal fluctuations in variable renewable supply and demand providing energy security and reliability.

“This process allows surplus renewable energy to be stored as hydrogen in the gas network and can be conserved and for later use converted back to electricity or used for domestic or industrial heat.”ena gas chart2

In this way, the report says, hydrogen from renewable electrolysis could improve the integration of renewable electricity generation into energy markets.

“We know that there is significant potential across the country to apply the transformational technologies of biogas, hydrogen and CCS to existing networks to build and maintain a highly reliable energy system,” said ENA chief Andrew Dillon in a statement on Monday.

“Hydrogen production and storage could be a game changer as it becomes more cost efficient as the technology matures,” he said.

“The majority of Australia’s gas distribution networks are compatible with hydrogen.

“With applied technology, our existing gas networks could deliver better outcomes for Australian households and businesses, the environment and the economy.”

Dillon called on governments to support the exploration of a broad range of options, including technology neutral policies that allow renewable gas to be injected into the network, encouraging more efficient use of biogas and other renewable gases.

Industry is testing the impacts of injecting biogas and hydrogen into networks, with trials underway.  

  • joono

    Queue anti hydrogen comments

  • Ian

    I wonder if the report factors in the fact that gas combustion appliances are only 60- 70%efficient, and heat pumps are around 400% efficient with energy utilization?….And therefore about half the running costs of gas.

    • AndrewATA

      I asked that question of an APA speaker at an industry event. He pointed to heat pumps run off gas-powered internal combustion engines! Unfortunately their efficiency is only around 200%, they’re only available in larger sizes and they don’t provide cooling, only heating.

    • The reports author’s missed the option being explored across Europe which is to make use of the existing natural gas grid as an energy storage system.

      This doesn’t need to be a permanent part of a zero-emission energy system. While battery capacity investment is ramping up, excess wind and solar power can be stored and distributed as hydrogen and/or methane in the existing natural gas system.

      Burning natural gas in heating appliances will eventually be discontinued, but for now, a large number of these appliances are being used. It will be some time before they are all replaced.

      Small distributed gas-fueled electricity generation can be up to 60% efficient. These do the job that batteries and pumped hydro will eventually do – when enough of them have been built.

      Farmers can add pressure on the coal seam gas industry by manufacturing methane from crop waste that is combined with hydrogen made to store renewable energy.

      When there are enough batteries and pumped hydro storage to eliminate the need for natural gas energy resources in Australia, this bio-methane can be used as feed stock in chemical industries to replace coal seam gas. It can also be exported as LNG, substituting for Australia’s coal and coal seam gas energy exports.

      • JonathanMaddox

        It may not have been mentioned explicitly in the summaries but since it’s a necessary implication (I haven’t read, or found, the full text of the report), I wouldn’t sweat it.

  • Ian

    What a hoot. By 2050 we should be able to genetically engineer reindeers to fly carrying presents to every house on the globe and genetically engineer pigs to eat waste and fart into the gas network to heat our homes and cook our dinners. We could then inject all this CO2 into the ground using the existing and highly economically effective CCS facilities that have already been developed using the $1/2 billion research money spent on this purpose.

  • Peter F

    Victorian households use about 100 PJ of gas per year 97% of it for space and water heating at about 70% efficiency. Using RC heaters with a COP of 4 that translates into around 20 PJ of electricity. or 5,000 GWh or the equivalent output of 700,000 five kW rooftop systems out of 2.7m small electricity customers, or 370-420 4 MW class wind turbines. Most heating is done away from annual peak demand so by using grid control of hot water services and adding hot water storage for space heating systems there is little or no need to increase the peak capacity of the electricity grid to de-carbonise the domestic gas system. In fact electric heating would improve the utilisation of existing assets including rooftop solar therefore lowering the unit cost of electricity

    • neroden

      Yep. To pile on, COPs are now higher than 4, rooftop systems tend to be larger than five kW, and so forth. Switching from gas to a heat pump is a no-brainer in *all of Australia right now*.

    • Ian

      Very sensible comment, and exactly correct. A re-look at home insulation may reduce the need for any form of energy for space heating. This is probably the time to retro-fit insulation and improve the building code for new homes and businesses.

  • derekbolton

    “zero-carbon gas network …through …and carbon capture and storage technology.”
    Ummm… no. Capturing CO2 from a fossil fuel power station and using renewables to convert back to methane which is then burnt is not zero carbon. The overall path is still from underground to atmosphere. It is only zero carbon if closed cycle, i.e. recapture all the CO2 from burning the gas. In that way, the gas is just an energy storage medium.