Australian utility tests compressed air storage
From: pv magazine Australia -
Compressed air energy storage is not exactly a new technology, but recent months have seen it get a new lease on life, as intermittent renewable sources of energy come to the fore.
Compressed air energy storage (CAES) is not much talked about in Australia, but perhaps that is about to change. A new CAES system from South Africa-based Leaper Innovate Green Energies (LIGE) – introduced to Australia by Queensland-based Essential Water and Energy Services – is unlocking the potential of CAES as a scalable energy storage system for clean intermittent sources with a long lifespan and low-cost.
CAES is not a new technology, of course. The first system (290 MW) was installed at Huntorf, Germany, in 1978 and is still in operation today. In 1988, the Alabama Electric Cooperative’s 110 MW CAES plant also began operations in North America. CAES has become a more feasible solution in the last year and several large-scale projects have been announced in the United States, Israel and Canada.
The LIGE is a zero-emissions air battery that can be linked to the grid or a renewable energy source to provide clean energy and even clean water.
According to Essential Water and Energy Services’s managing director, Geoff Hill, “a 1 MW air battery can produce up to 5,000 liters of water a day in humid conditions. The amount of water produced varies depending on the humidity of the air, also no rare earth metals are used and all parts can be recycled.” That 1 MW system could be housed in a single 12-meter container and would require a 225 kW solar system to recharge 1 MWh of stored energy.
With a 30-year lifespan and a range between 40 kWh and 50 MWh in either three-phase 380 VAC 700A or 750 VDC 500A, LIGE air batteries are now being manufactured in Australia.
Hill says the growing need for scalable energy storage systems in the energy transition means that CAES and particularly the LIGE technology “may challenge lithium-ion’s dominant energy storage position.”
All OK, but keep on saving
Dec 18 2014 17:23 - Media24
Johannesburg - Eskom has called on all customers to reduce electricity usage, especially in the early evening (17:30 - 18:30).
It said power supply was expected to remain constrained but stable the rest of the week, as well as over the rest of the festive season.
The utility said the risk of load shedding was low, but the system remained vulnerable, meaning that any extra load or faults in the system might necessitate the need to implement load shedding.
It said with many industries winding down for the festive season, coupled with the return to service of some of the power generating units and building up of emergency reserves, Eskom was cautiously confident that it would be able to meet the demand during the holidays.
Eskom generators running again
Dec 17 2014 07:52- Media24
Johannesburg - Four Eskom generators, that had stopped working at three power stations, were functional again on Wednesday morning, an official said.
"As we speak now this morning, we have recovered those units," acting spokesperson Khulu Phasiwe said.
"The system is no longer as tight as it was. We have relatively stabilised the power system," he said.
He said the power utility needed to build up its diesel and water reserves, which it had used for the past few days as an alternative supplier.
The generators had stopped working at three different power stations on Tuesday. Phasiwe said the risk of rolling blackouts still remained, but was low.
In recent weeks, the utility has battled to keep the lights on since the collapse of one of its coal storage silos, diesel shortages, and maintenance issues.
On December 5, Eskom implemented stage three "load shedding". Stage one allows for up to 1000MW of the national load to be shed, stage two for up to 2000MW, and stage three for up to 4000MW.
On December 8, Eskom CEO Tshediso Matona denied that the state utility was in a crises.
SA Govt could announce more energy projects
Dec 13 2014 15:51- Media 24
The country is in the midst of a severe power crisis because of the government's failure to build any major new power stations since the end of apartheid in 1994.
It is also committed to introducing renewable into its mix of power generation, 95% of which is coal at the moment.
The so-called "Window 4" of its renewable energy bidding rounds has invited bids for a range of renewable projects such as wind, photovoltaic, biomass and small scale hydro-electric.
Feeding into the grid
A government source said: "On Monday we will reveal the names of the projects that are successful and also the megawatt for each project and the size of the plants we are going to build."
South Africa invited bidders to submit proposals to build coal-fired power plants on Friday.
The power crisis has seen South Africa's rand plummet to a six year-low as investors worried about the certainty of electricity supply.
The government appointed Deputy President Cyril Ramphosa to oversee the turnaround strategy for struggling state utility Eskom, that only has enough funds to operate until January next year.