BRYAN LEYLAND: Net Zero nonsense

Net Zero electricity by 2030 using wind and solar power is an impossible dream: the resources needed to carry it out don't exist. (“Net Zero” means that we do not burn gas and coal for electricity generation except, maybe, in dry years.)

The excellent report by the Interim Committee on Climate Change said that we would need fossil fuels for the foreseeable future to keep the lights on during windless nights and during dry hydro years. This report was shelved by the Government and superseded by a report that had minimal input from experienced power system engineers.

There is strong opposition to new large-scale hydropower and geothermal is limited to about 1000MW (and also emits CO2). So only wind and solar power can be considered. Unfortunately, the wind doesn't blow all the time and the sun goes down every night, so wind and solar power need long-term, large scale, low cost energy storage.

We need at least 4000 MW of unpredictable and intermittent wind and solar power by 2030 to meet load growth and replace the energy generated by 2000 MW of coal and gas fired generation. I have calculated that by then we will need something like 2000 MW of storage to store surplus energy from wet years and deliver it in dry years, and store surplus solar power from the summertime for use on winter evenings. Without it, high prices, shortages and blackouts are inevitable. It will be even worse in a dry hydro year.

There is no suitable storage technology available now or even on the horizon.

The Onslow pumped storage scheme cannot do the job because it won't be ready for 10 or 15 years and, anyway, it is not designed to be able to respond to unpredictable wind and solar power. To do that, it would need a very large lower pond and it does not have one. Anyway, it is impossibly expensive.

There can be no doubt that “net zero electricity by 2030” will crash and burn. Sooner or later, it will have to be abandoned.

So where does this leave the BlackRock proposal? BlackRock must know that an all renewable electricity system by 2030 is an impossible dream. I suspect that they are using New Zealand to add credibility to a corporate virtue-signalling exercise.

So what are the options for reducing emissions from electricity generation?

Top priority is to explore for more gas so we can keep the lights on in the short term and burn less coal. There is no other way of keeping the lights on at an acceptable price.

We could develop more hydropower on the Clutha and Waitaki Rivers and on the West Coast. This is certain to be strongly opposed by environmental groups. Moreover, it wouldn't be ready in time.

We could develop more geothermal power but the resource is limited.

Nuclear power is certainly an excellent option but the Small Modular Reactors that we need won’t be ready by 2030. Anyway, it will it take years for the decision-makers and the public to accept that modern nuclear power stations are the safest form of major power generation in existence and safely storing nuclear waste is not a particularly difficult problem.

But there is an option: accept the latest information from the IPCC technical reports that tells us that RCP 8.5 (which is an extreme emissions scenario for input into climate models) is now known to be highly unlikely and should be replaced by a more realistic scenario. If New Zealand followed suit, current predictions of future rapid sea level rise and a rapid rise in temperatures would be replaced by scenarios that can be managed by adaptation. The IPCC also says that the climate effects of methane have been overestimated by a factor of four. If this was accepted, farm emissions would no longer be a problem.

This leads us to a commonsense option: review man-made climate change! All the research that my friends and I have done demonstrates quite clearly that there is no scientific evidence based on real world data that supports the hypothesis that man-made greenhouse gases cause dangerous global warming. None! The Climate Commission, the Royal Society of New Zealand and the IPCC all told us that they have faith in the climate models (never mind that they have never made an accurate prediction) and they rely on the "consensus of climate scientists". Consensus has no place in science because it simply amounts to "We all say so, it must be true!” No one has been able to disprove the hypothesis that the climate changes naturally and man-made global warming plays only a small part.

Which leads to the obvious solution: abandon net zero, abandon the emissions trading scheme, stop subsidising electric cars, forget about agricultural greenhouse gases and rejoice that the increasing levels of carbon dioxide are making our plants grow better and making us all more prosperous.

Bryan Leyland MSc, DistFEngNZ, FIMechE, FIEE(rtd) is a power systems engineer with worldwide experience. He has been a climate sceptic for the last 25 years.