Comment

‘Renewable’ energy future needs scrutiny

Two influential economists – Paul Conway of the BNZ, and Xero founder Rod Drury – recently described the advantages to New Zealand of moving to 100 percent renewable electricity. Pat Baskett investigates whether this is what is planned.

This decade is set to be the decade of electricity. How we move about will increasingly depend on electricity, as will the heat for manufacturing. What is in doubt is how we produce it. Yes, even in New Zealand where we proudly claim 85 percent comes from renewable sources.

Two years ago Transpower issued a comprehensive report – Te Mauri Hiko Energy Futures. In 64 pages it set out a very sanguine analysis of options for the how the country might deal with the uncertainties of supply and demand. But it needs close reading, despite these heartening words from Transpower’s CEO, Alison Andrew. She wrote:

“The decarbonisation of New Zealand’s economy will depend on its renewable electricity base and will require widespread electrification of new parts of our economy, such as our transport and stationary energy systems.”

“Renewable” is the key word. It is the best way, according to Te Mauri Hiko, to meet demand which is forecast to double by 2050.

“A renewable future is the most affordable,” the document tells us. This will come from grid-connected wind and hydro, and from distributed solar with batteries that are becoming more efficient and affordable.

Moreover, solar will “place more control in the hands of consumers.” By 2050, 1.5 million homes, we are told, will have photovoltaic cells. “The economics of solar and wind are compelling.”

But the spanner in the works and the biggest challenge is the peak demand of winter, especially when a relatively dry year leaves the hydro lakes only half full. So the problem with renewables is their intermittency. The wind doesn’t always blow and sunshine hours become shorter in bad weather and as the nights lengthen.

Thus, on page 50, we get to the nitty gritty. Estimates indicate that by 2050, despite all we’ve read until now, New Zealand will need to build six or seven gas “peaker” plants to meet the estimated shortfall of a dry year. A peaker plant is one which can be quickly switched on when needed to boost supply.

The contradictions in this document are profound. Even the conclusion refers only to renewables: “…. electricity will increasingly become a distributed tool that consumers will generate and manage themselves at their homes. Transpower supports this. However, electrifying the New Zealand economy will depend upon many new large-scale, grid-connected renewable power stations to meet the nation’s doubling of electricity demand.”

Renewable? While we might laud the fact that the Huntly Power Station will burn only gas and no longer coal, natural gas is neither renewable nor clean. Yet Todd Corp continues to claim the gas it is developing in Taranaki, is “a reliable, affordable and clean source of primary energy”.

Here’s a brief recoup of the bad news on methane, the primary component of natural gas. 

It leaks at every step of its production and use and its damage is immediate and powerful. Methane’s initial burst gradually decays over decades but during the first 20 years it’s estimated by the Intergovernmental Panel on Climate Change to be 84 times more damaging than CO2. Subsequently it degrades into water vapour and the CO2, which lasts for centuries.

Under the Zero Carbon Act we are committed to reducing methane by the inadequate amounts of 10 percent by 2030 and 24-47 percent by 2050. Six or seven new gas power stations will push us in the opposite direction of increased emissions.

The main problem of meeting peak demand is not in our domestic use. It’s in the heat that is used by industry to fire boilers and industrial processes. This heat is largely produced in boilers heated by burning coal. The transformation to electricity will be expensive and need consistency of supply. It will often require new boilers, which could be designed to burn wood waste rather than using electricity – as does the boiler Fonterra recently installed at Studholme. 

The increasing uptake of electric vehicles, for public transport and eventually for larger vehicles and trucks, will also make large demands. So there is no doubt about the claim by the Electricity Networks Association in a recent newsletter that “the 2020s will be the decade of electricity”.

Why any should come from gas-fired stations is beyond comprehension. Is the problem here that a corporate structure exists and sees more profit in gas rather than embarking on large-scale solar or wind? Is the profitability of our major electricity companies threatened by the potential of solar “to place more control in the hands of consumers”? 

When the electricity that comes to our homes is charged at double the rate for commercial users, who could blame people for opting out? Community solar or wind-powered micro-grids with batteries for storage would be more efficient and certainly more resilient than a national grid backed up by gas peaker plants. They would also minimise the vulnerabilities of distribution down a network liable to blackouts from storm damage.

An element of volatility has always been linked to electricity prices but the latest change favoured by the Electricity Networks Association and the National Party needs questioning. Domestic, or low-volume users - most of whom are families - may face a daily charge of $2, up from the current 30 cents. This would come with a reduction in per-kWh price but would in fact result in an increase in what most households pay. 

The reason for the rise is said to be because high domestic users – thought to be large families who are also poor – are currently subsidising those who, because they have insulation and/or other efficiency measures, use less electricity.

This would be a fallible measure of social justice.  

What do we need to do? 

1. Expedite the change away from coal and gas to 100 percent renewable.

2. Urgently insulate all homes.

3. Reduce emissions from transport by prioritising electrified public transport and rail.

4. Research the use of local biomass to generate heat and electricity, locally.

5. Implement the conservation measures set out by the Energy Efficiency and Conservation Authority. The low-carbon society we’re headed for will use less energy and use it more efficiently. 

Emissions reductions and affordable electricity for all should be our priorities. As individuals, we are the fourth-highest carbon emitters in the world. A totally renewable electricity supply would go some small way to make up for this.

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