The effect of wind integration depends heavily on the system in which it is being integrated. These studies made numerous recommendations that could reduce the cost of wind integration. First, several of the studies concluded that larger balancing authority areas were better suited to managing wind variability than smaller balancing authorities (Charles River Associates, 2010; EnerNex Corporation, 2006, 2011; GE Energy, 2008, 2010). Large balancing areas reduced variability in net load and provided a large pool of generating units from which to manage deviations from forecasted net load. Balancing area consolidation is discussed in Chapter 5 .
Second, wind benefits from systems with greater flexibility in the generating portfolio, as more startups and shorter cycles are required to accommodate net load variability caused by wind (Charles River Associates, 2010; KEMA, 2010).
Third, robust transmission is also important, as this allows for the aggregation of wind and regulating units over large geographic areas (Charles River Associates, 2010; EnerNex Corporation, 2011; EnerNex et al., 2010; EWEA, 2009; GE Energy, 2010; NYISO, 2010). Without significant transmission enhancements, wind curtailment could be significant (EnerNex Corporation, 2011).
Finally, a number of market mechanisms have the potential to reduce the cost of wind integration, including increasing the frequency of scheduling in intraday and subhourly markets (Charles River Associates, 2010; EnerNex Corporation, 2011; GE
Energy, 2010), incorporating wind forecasts into the day-ahead markets (GE Energy, 2005a, 2008), and having wind participate in regulatory markets by providing regulation down through wind curtailment (Charles River Associates, 2010; GE Energy, 2008, 2010).
Several studies noted that wind generation reduced the amount of thermal generation that was used, freeing up additional generating units to respond to net load variability. This process reduced the profitability of these thermal units, however, and could lead to plant retirements that would reduce the plants available for regulation and load following, as noted in EnerNex Corporation (2011), GE Energy (2008), and NREL (2012). This issue requires further study.