Rooftop solar PV has boomed in the past 12 months but it is often accused of causing nothing but trouble. It is expensive, it doesn’t cut emissions, it misses the peaks and causes problems for network operators by creating a surge in voltage levels when too many are concentrated in a single area. A bloody pest, say some.
Gradually, though, the myths surrounding these issues are being unwound. Costs are falling, so when subsidies are removed it will cut emissions at no public cost. Now new technology, in the form of “smart inverters” are being developed to solve the very issues that solar PV is accused of causing, and will mean that solar PV can be used to optimise the performance of networks and reduce the level of peak loads. Rather than being accused of adding to costs, it will reduce the need for expensive network upgrades, which are currently budgeted at $45 billion and account for most of people’s rising electricity bills.
The concept of smart solar systems is being developed in Australia by Queensland-based consultancy Evolve Energy, and is being trialled as part of the Solar Cities program on Magnetic Island. It’s technical stuff, dealing with the concept of active and reactive power, and I’m not going to go there in detail (those who want to can find something here).
The basic concept is this: by attaching smart inverters to individual modules the voltage surges that have been the blight of local networks with a lot of solar PV are managed, to the point where the network barely notices their presence. And because they can generate active and reactive power, instead of making no contribution to the network when the sun goes down, the power of inverters can be used to reduce demand at time of peak loads.
“Smart inverters are designed to solve the problems before they start,” says director Grant Behrendorff. By making solar PV virtually invisible to the network, the smart inverters enable more solar PV to be added to the grid, solving a major issue at the moment where the rollout of solar PV has been blocked in some towns in WA, and restricted elsewhere, because the local network operators said they could no longer cope.
Still, like much of the smart technology and energy efficiency opportunities that exist for energy networks, it will need regulatory change to make it attractive. In this case it is how to reward the provision of reactive power, which is not normally paid. “It’s terrific that the solar array on my house can be used to support the network during peak period, but there is currently no mechanism to reward me for that,” Behrendorff said.
He was not the only person at the Ecogen conference in Brisbane lamenting the slow pace of reform in Australia’s energy industry, or expressing frustration about a system that encourages more air-conditioning, yet puts road blocks in front of solar PV, and is able to spend up to $45 billion on power network upgrades with little oversight or analysis of alternative options.
Much of the network expense is being directed to increased demand at peak times, caused by that increased use of air-conditioners. One tenth of the capital expenditure is dedicated to providing capacity to respond to peaks that occur for just 20 hours a year, one quarter of the nation’s retail electricity costs are caused by events that happen just 40 hours a year — and yet the network operators are still given incentives to sell more electrons and erect more poles and wires, rather than provide incentives to consume less.
Michael Zammit, from the demand management firm Enernoc, said the financial models of Australian energy networks needed to be turned upside down. “You just can’t keep generating money from kilowatt hours. It’s not going to work,” Zammit said. “A lot of the future generation is going to come from your own home, your own office, your own battery. This is the sharp end of the stick for smart grid.”
Zammit was particularly critical of the “gentailer” model that has allowed the biggest energy retailers who now dominate the market to also become the biggest generators, and to benefit from the price surges at peak times. “What does the price of electricity mean to them when they have a captive market? Nothing.” He was also critical of the culture of the energy industry. “They are engineers and they find it easier to build things to rather than talk to customers to try and solve a problem. We have to break that nexus, and provide incentives to pursue smart-grid solutions.”
However, as Judy Anderson — chair of the policy and regulatory working group with Smart Grid Australia — told the conference, the pace of reform at many levels of the energy network has been, and will be, painfully slow. A review into tariff reform, which could help pave the way for smart solutions, had been going for 18 months and would likely continue for another 12 at least. “It is long and slow,” she said. “This is unfortunate because we have got to get going.”
Anderson said smart grids in Europe had produced a 7.1% reduction in energy use and a 24% reduction in emissions because of better network management. The Italian utility Enel had invested $3 billion in a smart grid, and was generating savings of $500 million a year. “If we want a clean energy future, we need a smart grid,” Anderson said. “You can’t do it without it, it’s like having one arm tied behind your back.”
*This article first appeared on Climate Spectator