With the proposal of carbon neutrality goals, the installed capacity of new energy has grown rapidly, and the demand for large-capacity independent energy storage facilities has increased significantly. The New Zealand government has announced the estimated cost of the Lake Onslow pumped storage scheme and a multi-technology alternative. The Government will move forward with the next phase of the New Zealand Power Storage Project, looking at the feasibility of pumped storage hydropower and alternative multi-technology approaches to create a resilient, affordable, secure and decarbonized energy system in New Zealand.

The New Zealand Electricity Storage Project was set up to find a solution to the "dry year problem", when the lakes that feed the hydroelectric plants get low, causing more fossil fuels to be burned to make up for power shortages and often higher electricity bills . "This climate change initiative is investigating the ability of pumped hydro storage and alternative technologies to address New Zealand's electricity problems in dry years," New Zealand's Ministry of Business, Innovation and Employment said.

The cost of building a pumped hydro scheme in Otago's Lakeonslow is four times higher than previously expected. Energy and Resources Minister Megan Woods announced the $15.7 billion price tag on March 16 as part of the next phase of New Zealand's battery project - up from an initial estimate of $4 billion.

Pumped hydro storage involves two basins, with water pumped from the lower basin into an upstream lake when power is plentiful, then filtered back to generate electricity in dry years. These plans do not depend on precipitation.

Pumped storage collects and stores water in two places—an upper reservoir and a lower reservoir. Using excess electricity, water can be pumped uphill to the upper reservoir for storage. When electricity is needed, water from the upper reservoir is released through a steep drop to power turbines and generate electricity.

Woods said the government was working on a detailed business case for Lakeonslow's large-scale pumped hydro storage scheme, as well as alternatives. Alternatives would involve a range of technologies, including burning biomass, next-generation geothermal and green hydrogen, and a small pumped hydro storage scheme in the central North Island. Keywords: infrastructure, infrastructure construction, domestic engineering news, planning investment

Newsroom first reported that the government was considering a pumped storage scheme on the upper Mowango River. In her release, Woods did not specify whether this was a plan she wanted to expand, but said the North Island option "depends on the agreement with the iwi". An alternative portfolio scenario would cost about $13.5 billion, but would be much more expensive to operate than Lakeonslow, Woods said. "We've always known that any dry year electrical energy storage solution would require significant investment, which is why it's important that we thoroughly test these scenarios and make sure they're correct," she said. "Now that some more detailed work has been done, we have a much clearer picture of the projected cost, which is very different from the high level of costing in 2006. The next stage will be to dig a little further before considering spending such a huge amount funding, but one thing we know is that doing nothing to address climate change is not an option.” Editor/Xu Shengpeng