708.8 MW Batteries (0 MW) + Natural Gas Fired Combined Cycle (706 MW) + Solar Photovoltaic (3 MW) operating in Marshall, IA — Midcontinent Independent Transmission System Operator, Inc..
708.8 MW
Nameplate Capacity
5
Generators
units
Hybrid (3)
Technology
Batteries + Natural Gas Fired Combined Cycle + Solar Photovoltaic
2017
Operating Since
Coordinates
42.0433, -92.8728
County
Marshall, IA
Nearby Plants
| Field | EIA | GEM | Wikidata |
|---|---|---|---|
| Operator | Interstate Power and Light Co | Interstate Power and Light | — |
| Owner(s) | Interstate Power and Light Co | Alliant Energy | — |
| Status | Operating | operating | — |
Marshalltown Generating Station is a 708.8 MW hybrid power plant located in Marshall County, Iowa. The plant, which began operating in 2017, is owned by Alliant Energy and operated by Interstate Power and Light Co. It is fueled primarily by natural gas and utilizes combined cycle technology. The facility also incorporates batteries and solar photovoltaic generation. Marshalltown Generating Station is connected to the Midcontinent Independent Transmission System Operator, Inc. (MISO) balancing authority and resides within the MRO NERC region.
The plant consists of 5 generators and features a 0.6 MWh battery energy storage system (BESS) with a duration of 2 hours, utilizing lithium-ion battery chemistry. The solar component employs a fixed tilt tracking system. In its latest year of reported generation, the plant produced 3,177,931 MWh, resulting in a capacity factor of 51.2%. The installed cost of the plant was $1012.11 per kW, according to FERC data. Marshalltown Generating Station is ranked as the largest of 13 power plants in Iowa and 304th out of 945 plants nationally.
Generated from EIA, GEM, and public data sources
NERC Region
MRO
Balancing Authority
Midcontinent Independent Transmission System Operator, Inc..
Grid Voltage
161 kV
Regulatory Status
RE
Entity Type
Investor-Owned Utility
Sector
Electric Utility
225.9K MWh
Latest Month
3.2M MWh
Annual Generation
51.2%
Capacity Factor
$1,011/kW
Installed Cost
$18.7/MWh
Operating Cost
Interstate Power and Light Company
Reporting Utility
Annual Capital & Operating Expenses
Cumulative Installed Cost
Per-Unit Cost Trends
Point of Interconnection
Nearest Substation
Marshalltown Generation Substation · 161 kV
Substation Distance
< 10 km
Operator
Alliant Energy
Coord Source
OSM spatial
Market Position
ISO/RTO Market
MISO
LMP Node
ALTW.CC.MGS2
Pricing Hub
MINN.HUB
Location Type
Generation Node
Node Source
EIA-860 direct report
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