Batteries Are Cheaper Than Peaker Plants. The Grid Queue Is the Holdup.

The cost argument for grid-scale storage is settled. In most markets a four-hour battery system now undercuts a new gas peaking plant on levelised cost for the same service, and the gap has widened for four consecutive years. What has not changed is how long it takes to connect one, and that number is now the thing determining how much storage gets built.

The bottleneck moved from a spreadsheet to a filing cabinet, which is a harder problem to solve because nobody’s cost curve fixes it.

The queue, in the only terms that matter

Interconnection queues in most large markets contain multiples of the capacity that will ever be built. That is not inherently a scandal; speculative applications are cheap to file and many were never serious. The problem is what the volume does to timelines for the projects that are serious.

Three structural features do most of the damage.

• Serial study processes. Each project is studied against the assumed presence of everything ahead of it. When a project ahead withdraws, downstream studies can require redoing, which cascades.
• Cost allocation uncertainty. A project’s network upgrade cost is not known until late in the process and can change dramatically based on the behaviour of unrelated applicants. Financing around that uncertainty is expensive.
• No meaningful entry cost. Where deposits are small relative to project value, filing broadly is rational, which inflates the queue that everyone else must be studied against.

We can procure a battery system in nine months and energise it in four years. Nobody in this business is waiting on cells.

Why storage suffers more than it should

Storage is disadvantaged by queue processes that were designed for generators. A battery is a flexible asset whose grid impact depends on how it is dispatched, but most study processes evaluate it at maximum output as though it were a thermal plant running at full load.

That assumption inflates the network upgrades attributed to it. Several markets have introduced flexible or limited interconnection arrangements, where an asset accepts curtailment during constrained periods in exchange for a faster and cheaper connection. Where those arrangements exist and are well designed, they work: connection timelines fall substantially and the operational cost of accepted curtailment is usually far lower than developers feared.

Adoption is uneven, and the details matter. A flexible connection with unbounded curtailment risk is not financeable, so the arrangements that succeed cap the exposure.

Queue reform, and what actually moved the needle

The reforms with the best measured record share a common shape: they impose a cost on occupying a queue position and study projects in groups rather than one at a time.

Cluster studies replace serial evaluation with batched analysis, which prevents the cascade problem and produces cost allocations that are stable enough to finance against. Higher, escalating deposits push out applications that were never going to be built. Readiness requirements, such as demonstrated site control, do similar work.

Markets that implemented both together have seen queue volumes fall and completion timelines improve. Markets that raised deposits without reforming study processes mostly just made speculation more expensive without accelerating anything.

The part that is genuinely hard

Some of the delay is not process at all. It is transmission. Where the network physically cannot carry additional output from a location, no reform to study methodology changes the answer, and building new lines takes the better part of a decade largely for permitting and land reasons.

That is the residual problem, and it is the one that will still be here after queue reform is done. Storage helps at the margin because it can absorb generation that would otherwise be curtailed, which is one of the better arguments for co-locating it. But it does not substitute for wires.

For the adaptation side of the same infrastructure question, see our reporting on how cities are budgeting for heat.