Alliant Energy Raises 2026 Load Growth Outlook as Data Center Expansion Accelerates

What’s driving Alliant Energy’s higher 2026 load growth forecast and O&M margin uptick—and can it last beyond the near term?

1) Higher 2026 load growth forecast: what appears to be behind the “raise” and why it matters

Management indicated that the 2026 load growth forecast was increased to 2%–3% (from 1% previously), and the key question is whether this is due to data centers ramping faster or better growth from the core customer base. ¹

From the discussion, both components appear to be contributing:

• Data centers ramping faster than expected

  • Management said there are positive developments including that “data centers [are] going a little bit faster than we expected” and that this provides uplift. ²
  • They tied this to specific projects and ramp progress: Google energized transmission service in Cedar Rapids with ramping to follow the contracted load schedule, and QTS initial energization of 300 MW anticipated later this year; Meta entered vertical construction in Beaver Dam. ³

• Core business performing better than originally expected (suggesting broader demand strength rather than only one customer)

  • Management also attributed the uplift to core business strength: other parts of the service territory are “doing better than we originally expected.” ²
  • Importantly, they explicitly resisted the idea that this is temporary, stating: “I don’t think that that’s temporary” and framing it as connected to ongoing economic impacts. ²
  • They further gave a concrete mechanism for regional spillover economics from data center construction: in Cedar Rapids, two projects (QTS and Google) have in excess of 10,000 workers, in a city of about 150,000, and management described that as driving hotel/restaurant and ancillary usage, i.e., supporting local demand beyond the direct load itself. ²

Why management thinks the forecast change is not purely “near-term”

Even though much of the incremental load is tied to data center projects (which can be “lumpy”), management’s sustainability argument is that:

• Temperature-normalized sales and broader customer performance provide room to continue investing in reliability and customer service. ⁴²
• The demand strength is tied to economic impacts that are plausibly persistent during the buildout and ramp period (including spillovers), not just a one-off. ²
• The load growth program is anchored in a longer plan: management described an expectation of a 60% increase in demand by 2031 through five executed electric service agreements. ³

2) O&M margin uptick: what’s changing and whether it’s “one-time” vs a higher run rate

The question you asked points to an O&M margin improvement by about 1 percentage point and whether that’s due to one-time factors already occurring or a structural run-rate improvement (e.g., inflation effects). ¹

In the provided excerpts, the clearest operational explanation given is about the timing of higher expenses in the first half and a lighter second half, rather than management explicitly confirming that costs are structurally lower. Specifically:

• Management expected higher expenses in the first half and said part of this relates to the timing of generation outages, implying a seasonal/timing profile to O&M. ⁴
• They said the first half is “pretty much what we had expected,” while the second half “will be a little bit lighter,” suggesting the margin movement may be driven partly by timing rather than a permanent reduction in cost structure. ⁴
• On the earnings drivers, they noted that year-over-year ongoing earnings were primarily driven by higher revenue requirements and other positives, but with offsets including higher operations and maintenance expenses related to growth of the business. ⁵
  • That framing implies O&M is still expected to rise with business growth, which is more consistent with a mix of timing and efficiency/price offsets than with a purely “one-way” permanent margin expansion story. ⁵

Temperature effects are not “O&M margin” per se, but they matter for the same period

While not exactly your O&M question, management also highlighted that milder-than-normal temperatures reduced electric and gas margins versus the prior year in Q2 (and by implication pressure the margin bridge). ⁵ They described temperature-normalized sales as an opportunity allowing continued investment. ² So the margin narrative in any given quarter/year can be influenced by weather normalization as well as O&M timing. ²⁵

3) Are the load growth and O&M margin drivers sustainable beyond the near term?

A) Load growth sustainability: plausible beyond near term, but project cadence and execution risk remain

The excerpted evidence supports greater confidence than “temporary” demand because management linked the uplift to:

• Faster-than-expected data center development, plus
• better-than-expected core performance attributable to ongoing economic impacts, not a temporary blip. ²

They also described an ongoing pipeline framework (e.g., 2–4 GW of potential future load currently in the customer pipeline). ³ That supports the idea that the raised 2026 outlook is connected to a continuing load-growth engine rather than a one-year artifact. ³

However, sustainability isn’t guaranteed because:

• Large-load ramps are inherently lumpy and depend on counterparties meeting conditions like land control, load ramp, and transmission/generation readiness. ⁶⁷⁸
• Management emphasized the need to avoid surprises and manage risk in how these large loads come online. ⁶⁷
• They also described resource plan clarity and future EPS/CAGR guidance as tied to the third quarter resource plan update, implying the ramp and longer-term economics will still be refined as execution becomes more visible. ⁹⁵

Bottom line on load growth: The raised forecast is supported by both early data center ramp progress and broader demand strength, with spillover economics cited by management; that seems more durable than a purely one-quarter factor, but long-term persistence still depends on project pipeline execution and readiness conditions. ²³⁷⁶

B) O&M margin sustainability: more evidence of timing effects than a guaranteed structural improvement

The clearest O&M-related explanation in the excerpts is that expenses are weighted to the first half and that the second half will be lighter, with generation outage timing cited. ⁴ That is consistent with near-term margin uplift that could fade when the cost timing reverses. ⁴

Additionally, management’s earnings bridge indicates O&M can increase with business growth (they explicitly mentioned higher O&M expenses offsetting positives in ongoing earnings). ⁵ That suggests that absent explicit efficiency initiatives or sustained offsets, you should be cautious about assuming a permanent O&M margin step-up. ⁵

Bottom line on O&M margins: The provided excerpts suggest the O&M improvement is at least partly driven by expense timing (first-half heaviness) rather than clearly confirmed structural margin expansion; therefore, sustainability beyond the near term is uncertain based on what’s disclosed here. ⁴⁵

4) Synthesis: what’s driving the forecast and O&M margin uptick—and what’s most likely durable

• Driving load growth higher (2026 2%–3% vs 1%):

  • Data centers ramping faster than initially expected and
  • core customer demand performing better, linked to ongoing economic impacts and cited local spillover effects from construction activity. ²¹³

• Driving O&M margin uptick:

  • The excerpts most strongly support that expense timing (e.g., generation outage timing) makes the first half heavier and the second half lighter. ⁴
  • The earnings framework also suggests O&M increases can be associated with growth, which argues against assuming a permanent margin lift without additional disclosed structural drivers. ⁵

• Sustainable beyond the near term?

  • Load growth: more plausibly durable because management describes it as not temporary and ties it to an active executed-ESA growth plan and pipeline scale, but still dependent on project execution and readiness. ²³⁷
  • O&M margin expansion: appears more timing-driven in the excerpts; sustainability is less supported unless future disclosures show structural cost efficiencies or continuing offsets. ⁴⁵