Alliant Energy

Alliant Energy Corporation is a Midwestern regulated utility holding company headquartered in Madison, Wisconsin. Its corporate roots trace to 1917, when predecessor entities began providing electricity in the region. The modern Alliant Energy Corporation was formed in 1998 through the merger of IES Utilities (Iowa Electric and Iowa Gas), Wisconsin Power and Light (WP&L), and Interstate Power Company. Alliant Energy is publicly traded on NASDAQ under the ticker symbol LNT and is an S&P 500 component. The company provides regulated electric and natural gas services through two primary subsidiaries: Interstate Power and Light Company (IPL, serving Iowa) and Wisconsin Power and Light Company (WPL, serving Wisconsin), reaching approximately 1 million electric customers and 430,000 natural gas customers across both states. Lisa Barton serves as President and CEO.

Alliant Energy's cleantech significance derives from its aggressive transition away from coal and toward renewables across its two-state service territory. The company has retired multiple coal plants in Iowa and Wisconsin and is replacing them with wind and solar capacity, positioning itself as one of the Midwestern utilities most actively executing a coal-to-renewables transition. Alliant Energy has become a major wind energy developer in Iowa — a state with some of the best wind resources in the US — with several large-scale wind farms in its generation portfolio.

Alliant Energy is also the developer and offtaker for significant solar projects across Iowa and Wisconsin, building utility-scale solar farms and working with industrial customers on renewable energy procurement. The company has committed to achieving net-zero carbon emissions from its electricity generation by 2050, with major interim milestones including significant coal retirement and renewable additions through the 2020s. Its capital investment program includes hundreds of millions of dollars per year in new renewable generation and grid upgrades.

As a regulated utility, Alliant Energy's cleantech investments are largely funded through regulated rate base — approved by state utility commissions in Iowa and Wisconsin — giving it stable, low-cost access to capital for long-duration infrastructure. Its scale ($4 billion annual operating revenue), geographic focus in the renewable-rich Midwest, and regulatory compact with two supportive states make it a significant actor in the US grid's energy transition.