At times, this 12000 MW of wind and solar power will be producing virtually nothing because the wind is not blowing and the sun isn’t shining. Our existing hydro and geothermal power can’t fill the resultant 4000 MW shortfall because there is not enough spare power available. As coal and gas are being killed off, the only option is to store the large amount of surplus energy available whenever the sun is shining and the wind is blowing. This can be as much as 4000 MW – something like 50% more than current demand.
We need a technology that can store all this energy when it is available and use it as necessary to cover the hourly, daily, weekly and seasonal fluctuations. Although many people believe that the 1200 MW Onslow pumped storage scheme could provide this backup, it cannot do so because it is too small, in the wrong place and it would need to have a very large lower storage lake.
In the words of Apollo 13, "Houston, we have a problem"!
To back up wind and solar, we need a large scale low-cost technology that can store and deliver up to half the existing power demand with time scales varying from a few hours to several weeks or even months. There is no suitable technology available or on the horizon. Without low cost storage, large scale wind and solar power cannot provide an economic and reliable supply.
4000 MW of hydro pumped storage in the North Island might work. But there is no chance of finding even one site with two large storage lakes close together with something like 500 metres difference in level that is capable of storing and providing more than 1000 MW for days on end.
The Government’s dreams of developing wind and solar power to eliminate the need for fossil fuels while providing a low cost and reliable supply are doomed.
A separate problem is the need for extra generation during dry years when hydropower generation drops substantially. Traditionally, this has been achieved by storing as much water as possible in our relatively small storage lakes, supplemented by gas and the coal stockpile at Huntly.
In 2019 the interim Committee on Climate Change produced an excellent report that told the government that it was a waste of money to aim for a “carbon zero” power system. The Government shelved this report and, in 2020, the Government set up the "NZ Battery Project” to look at ways of eliminating CO2 from power generation.
The prime objective of the NZ Battery Project is to investigate the 1200 MW Onslow hydro pumped storage scheme that has a large lake in a valley north of the Clutha river forming an upper basin that can provide all the extra energy needed in a dry year. According to the latest estimate from the Battery Project, it would take at least 11 years to build and cost $15 billion – about $12,000/kW, twice the cost of a geothermal station that generates day and night.
The scheme has many serious problems.
25% of the pumping energy would be absorbed by losses. Extra pumping would be needed to make up for evaporation losses from the lake. Pumping power would cost at least 5¢/kWh and maybe much more because, unless the electricity market is reformed, generators that have surplus power available for pumping would jack up their price the moment pumping starts.
The scheme’s major source of income would be from generating during a shortage. During the four months duration of a shortage, it would have to earn enough money to cover the capital charges and operating costs of $5 billion accumulated over the previous five years or so. This means that it would need to charge $1.6/kWh while generating. 10 times the current spot price!
But it gets worse: the way the market works, all generators would get $1.6/kWh so the extra cost of as much as $20 billion over the four month period would eventually be passed on to consumers. Every tonne of CO2 saved would cost about $7000. The current CO2 market price is only $85/tonne!
The common-sense alternative to Onslow is 1 million tons of coal on the stockpile at Huntly. Say $200 million to buy the coal plus about $40 million a year for capital charges and the like. Every time there is a dry year, the coal stockpile would need to be replaced and there would be a CO2 cost of $25 million. It should be easy to choose between $400 million or $20 billion every five years?
There are far better and cheaper options for reducing emissions of CO2 from power generation. More hydropower, more geothermal, substituting gas for coal and the most effective of all – clean, safe and reliable nuclear power.
Other options like hydrogen storage, batteries, compressed air storage, etc are all substantially more expensive than pumped storage hydropower. For instance, sufficient batteries to solve the dry year problem would cost $5 trillion.
The sooner the Government realises that a system dominated by wind and solar power cannot provide a reliable and economic supply and starts looking at cheaper and better options, the better.
Bryan Leyland is an electrical and mechanical engineer with 60 years experience in the power industry in New Zealand and overseas. This article was published HERE
We need a technology that can store all this energy when it is available and use it as necessary to cover the hourly, daily, weekly and seasonal fluctuations. Although many people believe that the 1200 MW Onslow pumped storage scheme could provide this backup, it cannot do so because it is too small, in the wrong place and it would need to have a very large lower storage lake.
In the words of Apollo 13, "Houston, we have a problem"!
To back up wind and solar, we need a large scale low-cost technology that can store and deliver up to half the existing power demand with time scales varying from a few hours to several weeks or even months. There is no suitable technology available or on the horizon. Without low cost storage, large scale wind and solar power cannot provide an economic and reliable supply.
4000 MW of hydro pumped storage in the North Island might work. But there is no chance of finding even one site with two large storage lakes close together with something like 500 metres difference in level that is capable of storing and providing more than 1000 MW for days on end.
The Government’s dreams of developing wind and solar power to eliminate the need for fossil fuels while providing a low cost and reliable supply are doomed.
A separate problem is the need for extra generation during dry years when hydropower generation drops substantially. Traditionally, this has been achieved by storing as much water as possible in our relatively small storage lakes, supplemented by gas and the coal stockpile at Huntly.
In 2019 the interim Committee on Climate Change produced an excellent report that told the government that it was a waste of money to aim for a “carbon zero” power system. The Government shelved this report and, in 2020, the Government set up the "NZ Battery Project” to look at ways of eliminating CO2 from power generation.
The prime objective of the NZ Battery Project is to investigate the 1200 MW Onslow hydro pumped storage scheme that has a large lake in a valley north of the Clutha river forming an upper basin that can provide all the extra energy needed in a dry year. According to the latest estimate from the Battery Project, it would take at least 11 years to build and cost $15 billion – about $12,000/kW, twice the cost of a geothermal station that generates day and night.
The scheme has many serious problems.
25% of the pumping energy would be absorbed by losses. Extra pumping would be needed to make up for evaporation losses from the lake. Pumping power would cost at least 5¢/kWh and maybe much more because, unless the electricity market is reformed, generators that have surplus power available for pumping would jack up their price the moment pumping starts.
The scheme’s major source of income would be from generating during a shortage. During the four months duration of a shortage, it would have to earn enough money to cover the capital charges and operating costs of $5 billion accumulated over the previous five years or so. This means that it would need to charge $1.6/kWh while generating. 10 times the current spot price!
But it gets worse: the way the market works, all generators would get $1.6/kWh so the extra cost of as much as $20 billion over the four month period would eventually be passed on to consumers. Every tonne of CO2 saved would cost about $7000. The current CO2 market price is only $85/tonne!
The common-sense alternative to Onslow is 1 million tons of coal on the stockpile at Huntly. Say $200 million to buy the coal plus about $40 million a year for capital charges and the like. Every time there is a dry year, the coal stockpile would need to be replaced and there would be a CO2 cost of $25 million. It should be easy to choose between $400 million or $20 billion every five years?
There are far better and cheaper options for reducing emissions of CO2 from power generation. More hydropower, more geothermal, substituting gas for coal and the most effective of all – clean, safe and reliable nuclear power.
Other options like hydrogen storage, batteries, compressed air storage, etc are all substantially more expensive than pumped storage hydropower. For instance, sufficient batteries to solve the dry year problem would cost $5 trillion.
The sooner the Government realises that a system dominated by wind and solar power cannot provide a reliable and economic supply and starts looking at cheaper and better options, the better.
Bryan Leyland is an electrical and mechanical engineer with 60 years experience in the power industry in New Zealand and overseas. This article was published HERE
6 comments:
Ah Brian, you know it makes no sense, I know it makes no sense and so do many others.
However, our govt is all about virtue signalling and optics. They want to go to the UN, puff out the chest and say “ look at us, World leading”
The fact the country is broke seems to matter not one jot.
A country full of resources to power itself and politicians who can’t organise a piss up in a brewery, will ensure the price we pay for electricity is high and unreliable.
Dunderheads in charge!
Great comment and knowledge, thank you.
It is well known that solar panels and wind turbine blades have about a 20 year life. The fact virtually nothing can be recycled from these, must be factored in. They all become landfill fodder.
Nuclear anytime for me.
Morning Brian
I have always wondered why we haven’t investigated the possibility of building a huge new dam, at least as big as the Clyde High dam, to replace the existing Tuai dam at Waikaremoana outlet.
That would provide an option that is closer to the industrial north and somewhat less expensive but more efficient than the Lake Onslow proposal. But who am l to ask these sort of rudimentary questions.
It just sounds like a bad idea doesn't it. Wind and Solar. An environmental problem.
Agree, optics seem more important to the current Government than a practical solution. Nuclear is the best option currently available to us. Economics matter, we need to be able to afford whatever we do to solve the energy shortfall, but continued CO2 emissions justified by virtue of being affordable doesn’t help with reducing our impact on climate change.
You are familiar with power generation costs. You know 12000MW does not cost 500 billion
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