Power shortages during winters when there is not enough water, wind or sun remain the Achilles heel in New Zealand’s otherwise huge potential to move most of its fossil fuel-driven economy to renewable electricity, says a new report from the national grid operator, Transpower. Entitled Te Mauri Hiko, the report suggests fast-starting power stations using natural gas should not be closed “without an energy storage solution” under scenarios that show the gap between supply and demand during winter is likely to balloon as the electricity system moves towards 100 percent renewable generation. None of the existing and emerging technologies for electricity storage solutions are obvious solutions, since battery storage will only fill in short-term gaps in supply and emerging technologies such as storing hydrogen as ammonia for use in power plants and nano-technological solar power generation are in their infancy. While a geological basin in Otago could be flooded […]