As utilities plan billions of dollars in new generation, transmission, and reliability assets, the most important question for residential customers is not whether growth occurs, but who pays for it . Electric systems are built to last decades, and once investments are approved, their costs flow into rates for many years. If large new users do not pay the full cost of the infrastructure they require, those costs are quietly shifted onto households and small businesses. This article examines how that risk plays out in Georgia first, then North Carolina, and then South Carolina , where utility structures are more complex. Georgia: rapid growth and the cost-causation stress test Georgia represents the clearest example of the challenge. Georgia Power’s long-term planning reflects extremely large projected load growth, with data centers comprising a dominant share of new demand. The scale and speed of this growth have forced the utility to plan for large additions of generation capacity and supporting transmission on an accelerated timeline.

The central regulatory question in Georgia is whether large new loads will bear their proportionate share of these costs . Georgia regulators and the utility have emphasized special rate structures, negotiated contracts, and commitments intended to protect existing customers. However, the financial risk remains if projected demand does not fully materialize or if customers exit early. In that case, long-lived assets—power plants, transmission lines, and substations—remain in the rate base, and residential customers may still be required to pay for them.

Georgia illustrates how “spreading costs” can work in two directions. If growth occurs as projected and contracts are enforced, fixed costs can be shared more broadly. If growth slows or reverses, the same mechanism can expose households to higher bills for infrastructure built to serve others. North Carolina: embedded growth and limited visibility North Carolina’s situation is more subtle but no less important. Duke Energy’s planning for North Carolina embeds data center growth within a broader mix of population growth, electrification, and industrial expansion. Unlike Georgia, Duke’s public filings generally do not isolate data centers as a standalone category in headline summaries, making it harder for the public to see how much of the projected build-out is driven by large, discrete customers.

From a cost perspective, Duke has acknowledged that its long-term plan implies average annual bill increases over the coming decade , driven by new generation, transmission upgrades, and reliability investments. The key issue is transparency. When large loads are embedded within aggregate forecasts, it becomes difficult for regulators and the public to assess whether those loads are paying the incremental costs they create.

North Carolina highlights a structural challenge in regulation: even when utilities act in good faith, limited disclosure makes it harder to enforce strict cost causation. Without clear separation of large-load impacts, residential customers must trust that negotiated agreements adequately protect them. South Carolina: multiple utilities, shared risks South Carolina presents the most complex case because it involves multiple utilities with different planning roles , most notably Dominion Energy South Carolina and Duke Energy Carolinas, along with Santee Cooper in parts of the state.

Dominion Energy South Carolina has been explicit in its Integrated Resource Plan that major new firm capacity—particularly a large joint natural-gas combined-cycle facility—is central to meeting future demand while managing cost risk. Dominion’s filings emphasize that alternative portfolios without this firm resource result in significantly higher long-term costs  due to reliability risks, market exposure, and the need for emergency or short-notice resources. From Dominion’s perspective, delaying or fragmenting major capacity additions could ultimately increase customer bills rather than reduce them.

At the same time, Duke Energy’s situation in South Carolina adds another layer. Duke serves a large portion of South Carolina load under the same Carolinas planning framework used for North Carolina. Duke’s forecasts include population growth, industrial expansion, and data centers across both states, but implementation and cost recovery occur at the state level. This creates tension: South Carolina customers may be paying for assets planned on a regional basis, while large new loads may not be evenly distributed geographically.

In South Carolina, the cost-causation challenge is therefore twofold. First, regulators must ensure that large customers—especially new industrial and data-processing facilities—pay for the incremental generation and transmission they require. Second, they must ensure that regional planning does not obscure state-specific impacts on residential bills.

Why this matters to customers Across all three states, the same principle applies: electric rates are driven less by energy use and more by infrastructure decisions made years in advance . Once assets are approved and built, their costs are largely unavoidable. That is why the timing of regulatory decisions, the structure of large-load contracts, and the transparency of utility planning matter so much.

If regulators rigorously enforce cost causation—requiring data centers and other large users to fund the capacity, transmission, and reserves they drive—residential customers can benefit from growth without being exposed to undue risk. If they do not, households may face steadily rising bills for infrastructure built to serve others.

The next and final article in this series will focus on why transparency and public oversight are essential to maintaining trust in this process, and how openness can help communities understand—and influence—how electric system growth unfolds over the next decade.