Microturbine-solar combo handles load variations of 250 kW every eight seconds

Optimal Group Australia, Capstone Turbine's exclusive Australian distributor, recently commissioned an innovative energy project for Santos Limited, one of Australia's largest independent oil and gas producers in the Asia- Pacific region, supplying energy needs across Australia and Asia.

The project required Optimal to deliver a stand-alone system to power one of the Santos remote oil production facilities as they wanted to replace their aging and inefficient reciprocating engine-based power system at their Tarbat Oil Production Facility in Southwest Queensland. In addition, Santos also wanted to achieve significant emissions reductions as part of the energy system upgrade. Inclusive in this requirement was the need to incorporate solar photovoltaic (PV) into the remote system.

The new energy system consists of a C1000S one-megawatt Capstone microturbine running on on-site natural gas from the facility. The system also includes a 250-kilowatt (kW) solar array and Optimal's proprietary Grid Stability Module (GSM) to stabilize the electrical load to address the project complexity of the new energy system which operates under significant load fluctuations resulting from the cyclical electrical loads that fluctuate as much as 250 kW every 8 seconds.

The system has cut the fuel requirements by 50% and as such is expected to reduce annual fuel costs for the facility by $1 million a year, delivering a very attractive financial payback for the project. As the system reduces Santos' natural gas use by half, it also reduces their carbon emissions by half for the site, while also dramatically decreasing the annual system maintenance required.

In developing this solution, Optimal incorporated its GSM into the system architecture. The GSM is a load response module incorporating proprietary Ultra-Capacitors and conventional lead-acid battery storage. The capacitors rapidly charge and discharge, thereby "absorbing" the significant load fluctuation without losing the available energy.