An electrical system must always be in balance. That means the amount of energy we generate or buy must meet but not exceed customer demand, also known as load.
Demand for electricity is not constant. It changes moment to moment, every time a customer flips a light switch, turns on an irrigation pump or shuts down a factory’s conveyor belt for the night.
Idaho Power has a responsibility to meet customers’ needs, no matter how they change, 24 hours a day, 365 days a year.
Federal law also requires us to buy all energy, often at greater cost than our own generation or market purchases, from certain wind farms, solar arrays and other clean energy sources whose output can change quickly and unexpectedly. Integrating these sporadic resources to match customer demand requires us to increase or decrease energy from our own power plants and buy or sell energy on the market.
The chart below shows which resources are contributing to meet constantly changing energy demand. Notice how these resources’ production varies each hour to meet customer demand and adjust to fluctuating generation from sporadic sources like wind.
Hydroelectric power provided nearly half of the energy delivered to our customers in 2018. For more details, see Energy Sources.
Click on a bar below to get detailed information on hourly output from each generation source.
Items on the chart are measured in megawatts. A megawatt is enough power to light up 10,000 100-watt bulbs. On average, a megawatt can meet the needs of 695 homes.
- Energy from coal plants co-owned by Idaho Power.
- Energy from diesel-powered turbines owned by Idaho Power (used on rare occasions).
- Electricity from hydro, coal, wind, solar diesel, etc.
- Energy generated by 17 plants Idaho Power owns on the Snake River and its tributaries.
- Idaho Power customers’ total energy demand.
- Nameplate capacity is the number registered with authorities for classifying the power output of a power plant.
- Natural Gas
- Energy from natural gas-powered turbines owned by Idaho Power.
- Net Purchases
- The net amount of energy purchased and delivered to Idaho Power’s customers.
- Non-Utility Geothermal
- Electricity generated by underground hot water and purchased from a third-party producer. This does not include energy from customer-owned on-site generation.
- PURPA*/Non-Utility Solar
- Electricity generated by sunlight and purchased from a qualified facility or third-party producer. This does not include energy from customer-owned on-site generation.
- PURPA*/Non-Utility Wind
- Electricity generated by wind turbines and purchased from a qualified facility or third-party producer.
- PURPA* Other
- Electricity generated by using water, biomass, landfill gas or natural gas and purchased from a qualified facility.
* PURPA- The Public Utility Regulatory Policies Act (PURPA) is a federal law that requires Idaho Power to purchase renewable energy produced by certain Qualifying Facilities (QFs), such as wind, solar, geothermal and small hydroelectric resources. The generation produced by these projects is identified as PURPA with the resource type (e.g. PURPA Wind). PURPA Other includes all non-wind generation produced from QFs that contract with Idaho Power through the PURPA process.
When the hourly generation profile exceeds the load line, Idaho Power is a net exporter of energy and has sold energy to a neighboring utility on the open market. The net amount received of these surplus energy sales (either profit or loss) is passed on to customers through the annual Power Cost Adjustment (PCA).
Idaho Power sells (or does not own) the renewable energy certificates (RECs, also known as “green tags”) associated with certain clean-energy projects in our energy mix. Proceeds from REC sales benefit customers. Idaho Power does not claim that clean energy from these projects is delivered to retail customers.
All information on this page is subject to change upon final review.