LAUNCESTON, Australia, Oct 28 (Reuters) - Australia"s widely criticised plan to reach net-zero carbon emissions by 2050 shows the scale of the global challenge ahead of the Glasgow climate summit, namely achieving real, actionable commitments instead of vague and hopeful statements. The problem is not that Australia, the world"s largest exporter of liquefied natural gas (LNG) and number two in coal, has belatedly adopted a net-zero goal for 2050, it is that the plan lacks details and relies largely on optimistic assumptions, unproven and yet-to-be invented technology.Prime Minister Scott Morrison, who leads the conservative Liberal-National coalition government, has defended the plan as "right for Australia", and dismissed critics as those who want to shut down industries and destroy livelihoods. The government"s pathway to net zero, revealed on Oct. 26, lays out a broad plan to reduce emissions to net zero by 2050. read more Using 2005 as a base, a graphic released by the government showed emissions reductions of 20% have already been achieved, although several environmental analysts dispute that claim, citing changes in how the government calculated emissions. Even if the government figures are accepted, the 2050 plan relies heavily on changes in technology.For example, 40% of the remaining reduction in emissions is to come from the Technology Investment Roadmap, and the government aims to invest A$20 billion ($15 billion) to support this process. What exactly this means is less clear, but it is almost certain to include spending on things like carbon capture and storage (CCS), carbon capture in soils and producing hydrogen from renewable energy, or from natural gas with CCS. The problem is CCS has had limited success, and where it has worked it has mainly been in upstream fossil fuel projects, rather than in end-user operations such as power plants and energy-intensive industries such as steel and cement. Carbon farming in soil is also promising, but there are doubts as to how much carbon can actually be sequestered through this process. The government also talked of something called "ultra-low-cost solar", again without spelling out what this really means. In addition to the 40% reduction planned to be achieved through technology, the government"s pathway also included a further 15% from changes in global technology and 15% more from "further technology breakthroughs". The remaining reduction is to come from domestic and international carbon offsets. Put another way, 70% of planned reductions in carbon emissions is to come from technology, topped up by carbon offsets for the rest. CLIMATE SCEPTICS It is not hard to see why Morrison"s plans were largely dismissed by climate scientists, energy experts and analysts. This is not to say that changes in technology will not be helpful, but it seems to be asking a lot for them to do virtually everything to meet Australia"s goal. Nowhere in Morrison"s plans are methods proven to work, such as a price on carbon, increased subsidies for renewable energy and electric vehicles, or a commitment to end fossil fuel investments and exports. The plan seems more political than practical, and is almost what you would expect if you forced a bunch of climate change sceptics to come up with a pathway that is more marketing spin than substance. Of course, Morrison"s government contains many noted climate change sceptics and deniers, and while a senior government minister, prior to becoming prime minister, Morrison once brandished a lump of coal in parliament, telling his opponents not to be scared of the polluting fuel. Morrison is certain to face criticism from his counterparts at the United Nations COP26 climate conference in Glasgow, which runs from Oct. 31 to Nov. 12. He will no doubt do his best to deflect this and stick to his script that Australia will chart its own course. If he is successful in this, he will show other countries that are reluctant to make meaningful changes to address climate change that style can perhaps triumph over substance.