Cutting power bills: It's about time
Tens of thousands of consumers could be able to pay different prices for electricity at different times of the day under a plan being worked on by Genesis Energy to smooth out peaks and troughs in demand for power.
Spokesman Richard Gordon said a business case for variable tariffs would be considered by the company's executive leadership team within three to six months.
Genesis has installed "smart" electricity meters in more than 300,000 homes that can record customers' electricity consumption by the half-hour.
Smart meters do away with the need for meters to be manually read. But some electricity companies and environmentalists hope they could also be used in conjunction with time-of-day pricing to encourage consumers to shift power consumption away from peak times, for example by only putting on tumble driers and dishwashers late at night.
Parliamentary Commissioner for the Environment Jan Wright said Genesis' plan was a positive development, but only so long as variable pricing was optional - as Genesis confirmed it would be - and people were given tools to monitor and control their power usage.
"If people are able to reduce power consumption at peak times, that reduces the need to build new power plants. It should be an option because often the people who cannot respond to peak prices are the poorer people who can't buy the latest equipment."
Gordon said Genesis would also announce specially discounted night electricity prices within the next few weeks for customers who bought Holden's recently released Volt plug-in electric cars, which are designed to be recharged overnight.
Genesis has carried out three trials of variable pricing, including a year-long pilot in Waitemata where 200 customers have been offered peak, off-peak and shoulder-rate tariffs for power.
The Waitemata trial has been followed by a similar trial involving about 50 customers in Christchurch and Genesis' "Tomorrow Street" project in which 15 mostly affluent households on Auckland's North Shore were offered hi-tech energy saving equipment and variable electricity pricing.
The business case for the wider launch of variable pricing would see Genesis offer time-of-day pricing in two parts of the country, which Genesis would not disclose for competitive reasons.
Electricity lines bills made up about 40 per cent of customers' total electricity bills and the potential for variable pricing to deliver savings to customers depended on the extent to which their local lines company was prepared to offer Genesis discounted off-peak transmission charges, Gordon said.
"You can't offer a very good off-peak rate at night without coming to some sort of arrangement with the lines company. Some have been very willing to work with us on this, others not so."
Consumers who took part in the Waitemata trial got an average annual saving of about $80 even if they made no change to their electricity consumption patterns, he said. Overall, the savings achieved were in single-digit percentages.
The households that participated in the Tomorrow Street trial achieved a much higher average saving of 19 per cent. Genesis provided up to $3000 of energy-saving equipment to each of those homes in the form of solar heating systems, EnerLogic energy-saving window film, Panasonic Econavi energy-efficient fridges and insulation.
Gordon acknowledged the trials showed many customers needed help and advice to exploit time-of-days tariffs. "It is not just a case of saying: ‘Here is a multirate tariff' and leaving the customers to figure out by themselves what to do. I think we have realised people do need some help."
Genesis has provided about 400 homes, including many of the Waitemata triallists, with wi-fi enabled power boards that let customers monitor and pre-set the times at which devices such as washers, driers and lights turn on.
Each home in that "Home IQ" trial received two power boards, two single-socket devices and a device hardwired to their modems - together worth about $1000 - that let them monitor and control their appliances over the internet.
"We have one solo working mother in Tomorrow Street who has done away with their tumble drier. What she is doing now is using Home IQ to put her washing on late at night and hanging it out in the morning before she goes to work."