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Large scale deployment of wind driven electrical power generators is hampered by the intermittent nature of the wind and thereby the high variability from any individual wind turbine.  When larger groups of wind turbines are connected over an extended geographical area, this issue is somewhat ameliorated, but there remains a residual variability that can still be quite large.  To add to the issue, the demands placed on the grid as a function of electrical utilization is also quite variable.  The nature of load variation is largely uncorrelated with the variability of the wind.  With current technologies there is no efficient method to store electricity in large quantities therefore it is necessary for the electrical grid to be able to rapidly follow this varying demand.

The difference between the demand and capabilities of generators must be balanced in real time to avoid a break down in the power distribution system.  As wind power becomes a greater and greater proportion of the national electrical power system this issue is brought to the forefront.  Existing turbines are very efficent at balancing when they are running at their designed condition (usually at or near 100% output).  However this efficiency drops off dramatically when the operating condition is varied off the optimal point.  So, while highly flexible, when this flexibility is exploited it comes at the expense of lower efficiency. Rapid or frequent ramp-up or ramp-down of the current systems also creates thermal stresses that result in shortened machine life and increased maintenance costs.

Stellar’s next generation turbine system is somewhat less efficient at 100% power than their existing counterparts.  However, it has a significant advantage when operated at a reduced power setting.  In fact when operated at 90% rated power or lower it is more efficient than the current state-of-the-art, by as much as a factor of 4 or 5 in parts of the operating region.  Stellar's turbine can then maintain an optimal condition for the turbine over a wide range of power outputs.  When deployed in combination with wind turbines, this new turbine system will provide an important bridging function that will allow the large scale deployment of wind turbines while maintaining the overall reliability of the electrical power distribution system.