Alliant Energy is a Madison regulated utility holding company whose investment case now turns on whether contracted data-center load converts into earned rate base without breaking the Iowa and Wisconsin customer compact. The second-quarter print reaffirmed full-year ongoing earnings guidance and placed results in the upper half of that band even after milder weather cut cooling demand. What changed is not the headline earnings number. It is the shift from a weather-and-rate-base story toward a large-load construction story that management already treats as the next growth engine.
Three named campus projects are already in physical construction under commission-approved electric service agreements. Google has energized transmission service in Cedar Rapids. QTS is building a seven-building campus in the same Iowa market, with initial energization of three hundred megawatts still scheduled later this year. Meta has entered vertical construction in Beaver Dam, Wisconsin, after the state commission approved an individual customer rate agreement. Those three events matter because they convert a pipeline slide into steel in the ground, which is the only form of load growth that regulators allow into rate base on a timely path. The mechanism is simple: contracted megawatts pull generation, storage, and transmission investment; those assets earn an authorized return only after commissions accept the spend as used and useful.
The tension is that the same load that justifies the capital plan also concentrates credit, construction, and political risk in a handful of counterparties and two statehouses. Second-quarter GAAP earnings of $0.65 trailed the year-ago print, even as six-month GAAP earnings of $1.52 edged ahead. Rate-base revenue requirements at Interstate Power and Light and at Wisconsin Power and Light each contributed nine cents of earnings, which means the quarter was purchased with capital, not with weather or with a surprise in authorized returns. Milder cooling degree days in both Cedar Rapids and Madison already showed how quickly the operating print can fade when the large-load ramps have not yet arrived. A residential natural-gas rate cut approved in Iowa in late August is a reminder that commissions still police customer bills even while they bless data-center contracts.
The next observable tests sit in the remainder of this year and in the 2027 through 2029 earnings-growth claim of more than seven percent. Watch whether QTS energizes on the contracted schedule, whether Meta's Wisconsin rate agreement holds through the first billing cycle, and whether the five executed large-load agreements begin to show up in weather-normalized sales rather than only in the slide deck. The equity already prices a clean conversion of that pipeline. Slippage on any of those three ramps, or a commission that starts treating data-center generation as a subsidy from existing customers, is what would reopen the multiple.