Wind models for intermittency and forecast errors.

Mitigating risk in wind power production and sale

The variable nature of wind power has a direct impact on the financial benefits of Power Purchase Agreements (PPAs). KEMA helps clients mitigate the financial risks inherent in wind farm PPAs through modeling both the intermittency and forecast errors and the plan and unplanned grid events leading to curtailments.   

 

Typically developers will enter a PPA that falls into one of two main categories – all at a fixed or market-based price over specified period or a fixed quantity based on “firm” agreement. In both cases the developer is at risk from unforeseen events that are difficult to quantify.

 

Modeling wind farm output, grid operations reliability and curtailment

KEMA relies upon a variety of modeling tools to estimate the net cost of unforeseen intermittency and forecasting errors. Our process begins with standard wind resource assessment and the determination of a Park Power Curve (PPC), which is either provided by the developer or estimated using advanced wind modeling software that utilizes local wind data, elevation and topographical maps as well as turbine power curve specifications.

 

With our proprietary KERMIT model, KEMA has the capability to model both planned and unplanned system events that give rise to curtailments. KERMIT also can model forecasting errors as a deviation from scheduled production by incorporating realistic “hind-casts” of state-of-the-art forecasting methods (i.e. numerical weather prediction, neural networks or other). In addition to system frequency and regulation quality, KERMIT also models market prices and volumes as well as information on plant emissions.