- Back-up is always provided for all power plants on a system, with or without wind
- There is no need to build back-up for wind; existing power plants in any system provide the required back-up for all plants
- Wind generation displaces fossil-fuel generation and some of those plants can be taken out of operation
- As the penetration of wind increases in any power system, the volume of capacity that is operated at part load, ready to ramp up or down according to peaks in demand or unexpected generation shortfalls, increases slightly to maintain a consistent probability of security of supply
- Since the volume of extra reserve when adding wind is modest so is the additional cost. Savings from wind replacing other generation are likely to more than cover that extra cost
- The emissions saved by wind displacing fossil-fuel generation are far greater than any extra emissions from increased spinning reserve.