John Raine & Bryan Leyland: A Realistic Energy Future

The 23rd July 2025 USA Department of Energy (DoE) Report, “A Critical Review of Impacts of Greenhouse Gas Emissions on the U.S. Climate” [1], authored by five eminent scientists, brought some balance back into the climate change debate, and outrage from many in the climate science community. The report exposed significant alarmism in the UN Intergovernmental Panel on Climate Change (IPCC) statements on anthropogenic carbon dioxide (CO2) and climate change, projected temperature rise and extreme weather events. The DoE report is against apocalyptic projections, far more moderate in its findings, and underlines the fact that science is NEVER settled. In a recent article [2], it was noted that:

· CO2 is necessary for plant life, therefore human life on Earth.

· Anthropogenic CO2 contributes less than 5% of the long-term CO2 in the atmosphere. Global warming from an improbable doubling of CO2 would produce further greening of the Earth including increased agricultural productivity, while very unlikely to cause a temperature increase beyond 0.5 – 1.8°C (and likely towards the lower end of this range).

· Human activities contribute about 1% to natural energy flows in the atmosphere.

While it may well be prudent to manage CO2 resulting from human activities, extreme Net Zero emissions policies are not justified when we are planning our energy future. This is made very clear by environmentalist and author, Michael Shellenberger, who argues persuasively in “Apocalypse Never” [3] against climate change alarmism.

Net Zero 2050 and New Zealand’s Energy Future

So far, the National-Act-New Zealand First coalition government still intends to abide by the 2016 UN Paris Climate Agreement and pursue Net Zero Carbon 2050, in spite of the fact that New Zealand’s 2023 gross CO2 emissions were less than 0.09% of the global CO2 emissions, so nothing we do can possibly have any measurable effect on global temperatures. Furthermore, Net Zero is economically unachievable - over $530 Bn cost for NZ [4, 5] (an upwards correction to the figure given in Reference 1) and unnecessary, especially as the atmospheric temperature effect of further CO2 increases is only minor.

The Western world is highly focused on renewable energy, driven largely by climate change concerns, political activism and the huge subsidies that many countries make available for wind and solar power. Wind and solar energy installations are proliferating. We have no problem with this technically, but the 28th April 2025 electricity grid collapse in Spain demonstrates what happens when there is excessive reliance on solar and wind power leading to grid instability. Another problem is that a careful analysis of electricity prices compared with the percentage of wind and solar power connected to a system, shows that in every case a higher proportion of wind and solar power leads to higher prices [6].

The cost of solar and wind at the station gate is falling, but they have a short life of 15 – 25 years, compared with 50 - 100 years for well-maintained hydro-electric plant. When this is combined with the need for fast-start back-up generation, wind and solar are very expensive from the point of view of the complete energy system. A perfect example is the astronomical energy price in the UK, as they pursue their dream of a wind and solar future, with other European countries and Australia in hot pursuit. These electricity generation options also have a significant environmental impact which including noise and the loss of valuable agricultural land.

Solar and wind can only be part of the energy supply equation. These are highly-variable-output, low-inertia systems that do not deliver when there is no sun or wind respectively. In the absence of viable battery technology for massive energy storage (as explained by Leyland [7]), they must be backed by high-inertia and high-density energy systems such as coal or gas fired, geothermal, or nuclear, turbine-powered plant (plus hydro when the lakes allow), equal to at least 50% of the wind and solar installed capacity.

The recently launched Genesis Energy battery system at Huntly, that could power 60,000 homes for only two hours, would be of minimal real help in a major outage. According to the 2023 census, there were a total of 542,349 occupied private dwellings in Auckland alone. Current battery technology is too costly and would require coverage of hundreds of square kilometres to meet New Zealand’s back-up needs in a high wind/solar energy future. It could easily cost close to $1 trillion and would need to be replaced every 15 years or so.

Michael Shellenberger [3] discussed how vested interests have demonised fossil fuel-fired (in particular gas-fired) and nuclear power plant in favour of solar and wind. He advocates for a balanced energy strategy, as is needed in New Zealand.

Technologically and economically advanced societies have come about through the availability of high-density energy. Developing nations need to be able to stop burning wood (low density energy) and access this through e.g. hydroelectricity and natural gas, even coal in the short-to-medium term. The UN has been wrong (and immoral) to push leapfrogging to wind and solar power for developing nations, as these options are expensive for reasons outline above.

New Zealand must hold to a high-density energy strategy and underpin its renewable electricity generation with base and intermediate load generation capacity which is provided by rotating machines to keep the system stable. We are fortunate in having a high proportion of renewable energy, particularly hydro and high-inertia geothermal turbine generator systems. A rational strategy should:

· Add more hydro and geothermal plant to the extent that this can be done economically. Additional wind and solar plant can be part of the mix but only for as long as dispatchable backup capacity is available.

· Ensure that we have enough base and intermediate load generation that provides low cost, reliable generation day after day. To manage dry years, this would be ideally from coal and gas-fired plant if there is sufficient gas and it is associated with gas storage so that it can be used when it is needed. Gas emits half the CO2 of coal but, until a large-scale low-cost storage technology is invented, coal is still a viable fuel, and if we need even more coal, we should mine our own rather than import coal from Indonesia.

· Include small modular nuclear reactors as part of the future. (as should be the case for many other countries also). Overseas, the outlook is promising especially as the regulatory regime designed for the reactors of 40 years ago is being rationalised in accordance with the needs of inherently reliable mass- produced reactors.

· Ensure that fossil fuels continue to be available for necessary transport operations. e.g. heavy transport, petrochemical industries, shipping and air travel.

As their whole life cycle economics and environmental impact mean that long-term prospects for electric vehicles seem uncertain, fossil-fuel powered personal transport should remain an option for the foreseeable future. Governments should incentivise the use of small, low-powered and efficient vehicles for general city use like the school run and shopping.

Ninety percent of the energy consumed in city transport is used in accelerating the vehicle up to speed and this is directly proportional to vehicle mass, so why drive around the city in a big SUV if you don’t need to? Fleets of driverless cars are also an imminent prospect and can be designed to minimise fuel consumption. Homes should be built to high insulation standards and make use of passive solar heating wherever possible.

Final Word

As previously noted [2], decisions for the economic and environmental future of New Zealand should be based on a dispassionate assessment of current science and real-world evidence, and not on UN exhortations based on the projections of computer models of extreme scenarios regarding climate change.

On the basis that CO2 has been unduly demonised we recommend a more nuanced approach for New Zealand where Net Zero is abandoned, our electricity generation system includes medium-term gas-fired (or coal if gas is unavailable) and small nuclear plants to ensure base load capacity, and our future transport needs are met with a mix of fossil fuel and electrical energy as appropriate. In this regard, a parliamentary cross-party accord is urgently needed. Without a unified policy we are doomed to high electricity prices, shortages and blackouts.

John Raine is an Emeritus Professor of Mechanical Engineering and a former researcher in alternative and renewable energy systems. He formerly worked in the UK engine and vehicle test plant industry.

Bryan Leyland is a semi-retired Electrical and Mechanical consulting engineer specialising in power systems. He has experience in almost every form of generation from nuclear power to wave power.

References

1. John Christy, Ph.D., Judith Curry, Steven Koonin, Ross McKitrick, Roy Spencer, “A Critical Review of Impacts of Greenhouse Gas Emissions on the U.S. Climate”, Report of the Climate Working Group to U.S. Energy Secretary Christopher Wright, USA Department of Energy, July 23, 2025

2. John Raine, “Balancing the Climate Narrative – The Science is Not Settled“ Breaking Views NZ 11thAugust 2025 https://breakingviewsnz.blogspot.com/2025/08/john-raine-balancing-climate-narrative.html

3. Michael Shellenberger, “Apocalypse Never: Harper Collins, © Copyright 2020 Michael Shellenberger. ISBN 9780063074767 international edition; ISBN 9780063001701 e-book

4. Michael Kelly, “Achieving Net Zero: A report from a putative delivery agency”. Note 30 The Global Warming Policy Foundation © Copyright 2022, The Global Warming Policy Foundation, UK.

5. Michael Kelly, “An Assessment of the NZ Resources Needed for Carbon Zero”, a presentation to Engineering New Zealand, 1 December 2020, Auckland.

6. Emil O. W. Kirkegaard, “Solar and Wind are Very Expensive”, Clear Language, Clear Mind Blog, 6 May 2025, https://emilkirkegaard.dk/en/2025/05/solar-and-wind-are-very-expensive/

7. Bryan Leyland, “An Analysis of Storage Needed for Large Scale Wind and Solar Power”. Paper to be presented at EEA Conference, September 2025.