Спрэд для электростанций: определение и применение в энергетической торговле.

The spark spread is the theoretical gross margin of a gas fired power plant from selling a unit of electricity, having bought the fuel required to produce this unit of electricity. All other costs (operation and maintenance, capital and other financial costs) must be covered from the spark spread. The term was first coined by Tony West's trading team on the trading floor of National Power Ltd in Swindon, UK during the late 1990s and quickly came into common usage as other traders realised the trading and hedging opportunities. The term dark spread, quark spread and bark spread refers to the similarly defined difference between cash streams (spread) for coal fired power plants, nuclear power plants and bio mass power plants respectively. These indicators of power plant economics are useful for trading energy markets. For operating or investment decisions published "spread" data are not applicable. Local market conditions, actual plant efficiencies and other plant costs have to be considered. A higher dark spread is more economically beneficial to the owner of the generator; an IPP with a dark spread of €15/MWh will be more profitable than a competitor with a dark spread of only €10/MWh. Further definition of clean spread indicators include the price of carbon dioxide emission allowances (see: Emission trading).

Spark spread can be used to assess the loss of revenue if a power station is switched from a normal running scenario to one where it is held in reserve to provide power when a large population of wind, or other renewable generators, is unable to generate. In theory, the power station operator would be indifferent to such non running as long as he was paid the spread it would have earned during the normally expected number of hour run. In fact, if paid the expected spark spread for the hours it had expected to run in normal operating mode, the operator would be better off, because it would not incur the variable operating and maintenance costs (O&M costs), which are proportional to the electrical energy produced. An assessment of the lost revenues is needed if some power plants, such as wind turbines, have absolute priority (must run plants). A dispatching authority will in this case order the other plants to decrease power. In some countries plant operators are entitled to receive compensation for such interventions. In a competitive electricity market the situation can be handled by a balancing mechanism, in which any imbalance from the schedule (typically a day ahead schedule) is penalized, either using the price from a balancing market or a calculated price. Thus, since UK spark spreads were in the range of 4–9 £/MWh – on average £6.5/MWh, or 0.65 p/kWh, we can assess the likely cost of relegating existing power stations to a standby role for a large penetration of renewables as being around 0.65 p/kWh.