Recently the energy debate in Australia has embraced two concepts that, up until now were pushed onto the fringes by politicians and media alike. In one week our PM is talking about battery storage and pumped hydro, with media dutifully reporting on them. This is a refreshing change from the previously polarised positions of pro-coal and anti-coal. It goes some way to explain the wicked problem power supply has become in Eastern Australia and maybe some way to examining solutions.
To some degree this debate started last September when large parts of South Australia were blacked out. The primary cause related to a number of transmission lines being brought down by severe storms. Further debate is fueled by concerns over the announced closure of Hazelwood Power Station next week. Experts in the field are predicting power shortages and consequent price rises, because the price of electricity is intrinsically linked to the supply and demand ratio. Hazelwood is majority owned by French company Engie, and they decide, if and when it will close, a decision made primarily on economic grounds. While I for one will not be shedding a tear for the closure of Australia’s major greenhouse gas emitting power plant, I do however have concerns about a French boardroom having such power of veto when it comes to Australia’s energy security and the lives of virtually everyone in the Latrobe Valley. Thirdly, the availability and price of gas has become an issue, this is mired in claims and counter claims. When burnt in a modern, efficient plant to generate steam to drive turbines to generate electricity, gas emits about half the CO2 that coal would in an equal new plant, hence gas producers claim that gas is a good transition fuel to reduce CO2 emissions. However the potentially very high fugitive emissions and environmental impacts of gas extraction can render gas as no better than coal. The greenhouse gas emissions are fueled by losses to the atmosphere during extraction and huge energy demands in processing and chilling the gas to minus 160 degrees to liquefy it for transport. By 2020 Western Australia’s CO2 emissions are set to double as a result of Wheatstone and Gorgon gas production and export. Furthermore the export of virtually all of Queensland’s gas production has led to cries of panic to support unconventional gas such as fracking. In Western Australia we have an agreement for some of the gas from the North West Shelf to be available for domestic use. In 2016 Chevron and Alinta signed a deal to guarantee 20 petajoules (1015 Joules) per year from 2020. The plant is anticipated to supply 73 petajoules annually. As such the argument for fracking in WA simply falls down. What I’ve tried to demonstrate is the complexity of the issues and the very large corporate interests with subsequently large budgets to secure the best deal for their businesses.
Having demonstrated the interlinking issues driven by vested interests, I will return to the emerging debate on batteries and pumped hydro. Each of these technologies can play a vital role in Australia’s energy future, particularly in regards to issues of peak demand and grid smoothing.
At the domestic level batteries can smooth demand, especially when combined with renewable energy generation. Simply they utilise power when there is surplus and deliver power when there is a shortage, resulting in a household significantly reducing their influence on the grid, and power bills. The monitoring regime at Josh’s House gives good data on this. The WGV development took this information and up-scaled for a whole housing development also being monitored for performance. CUSP, LandCorp and the City of Fremantle are now working on a larger area grid system named Greater WGV. It is hoped this will allow homeowners and businesses in a brownfield development to enjoy the benefits of larger scale battery storage, further smoothing their impact on the grid. At this level it can be seen as cloud storage for renewable energy. Single homeowners can store their excess energy and call on it when their demand is higher. This would also allow apartment dwellers for instance, who don’t have options for renewable energy generation, to connect to that cloud for access to renewable energy generated in their precinct. What I have just described is a long overdue move towards a smart-grid. The battery proposals from Tesla and Western Australia’s Carnegie/EMC go a whole step further by installing very large-scale battery system(s). At the moment it is not clear how these would be integrated into the grid. In Western Australia rooftop PV generates more power than any single fossil fuel power station. It is reasonable to expect home battery systems to replicate that share in the short to medium term, with larger battery supply being located in transformer yards to smooth peak demand and stabilise the system.
Australian’s have not heard much about pumped hydro, but internationally it is proved technology. Places like Scotland with large numbers of hydro schemes make very good use of it. The Snowy Mountains Scheme is a large hydro plant, where basically water is trapped at a dam and run through turbines into a holding lake where it is distributed to the river system. The proposal would be to pump water from the lower lake back into the dam storage so that same water can be used over and over again to generate electricity. The water is pumped when the grid has excess power and discharged through the turbines when the grid is short of power. In the south west of Western Australia there are many dams of varying sizes originally built for water storage. Unfortunately the drying climate has rendered them incapable of fulfilling their original role, through simple lack of capacity and salination. However, water is discharged from them to maintain river flows, and a simple turbine at the outfall could be used to generate power, if that outflow was regulated they could help in times of high power demand.
As I pointed out earlier there are a lot of vested interests in the power market and one of those relates to spot pricing. As demand reaches grid capacity the spot pricing escalates to the point that generators make the lions share of their profits on the few days the power systems are at breaking point. Smoothing the supply-demand profile with battery, pumped hydro or other technologies will be strongly resisted by those who profit from high spot pricing.
The last point I would like to make is that of demand management. We seem to be focused on supply management, especially when demand gets close to supply capacity. Another way of smoothing power systems is through demand management. There are many appliances that simply could utilise power at times of excess supply and switch off in times of high demand. I use SmartPower at home, whereby Synergy charge me about double to use power during high demand, which is offset by half price power at night. By simple demand management I can take advantage of this and save money. If a home has a pool or bore the savings become even more compelling. Likewise businesses with high power demands can tailor their usage to take advantage of varying tariffs. Again, a Smart Grid can send signals to appliances to achieve grid smoothing. Of course, electric cars add a while new dimension to battery storage, grid smoothing and power management.
It’s great to hear our leaders talking about batteries and pumped hydro, but first and foremost they need to reduce the influence of vested interests in shaping Government policy.