Sections 48E & 45Y: Two Clocks, Two Technologies

How the Two Credits Work

Sections 45Y and 48E replaced the legacy production and investment credits for projects placed in service from 2025, on a technology-neutral basis: any generation facility with a zero greenhouse-gas emissions rate qualifies, and standalone energy storage of at least 5 kWh qualifies under 48E regardless of how it charges.

Both credits share the same rate mechanics. The base is 6 percent (ITC) or 0.3¢/kWh (PTC); meeting prevailing wage and apprenticeship requirements — or being under 1 MW, or having begun construction before late January 2023 — multiplies it five times, to 30 percent and roughly 2.8¢/kWh (2025, inflation-indexed). The choice between ITC and PTC is an economics question: capital-intensive, lower-capacity-factor assets tend toward the ITC; high-output wind and solar historically toward the PTC.

The Wind and Solar Termination

OBBBA ended 45Y and 48E for wind and solar facilities placed in service after December 31, 2027 — unless construction began on or before July 4, 2026, in which case the facility keeps the standard four-year completion window and can reach service as late as 2030.

That deadline has already passed, which means every wind and solar project in the country now sits on one side of a line: grandfathered by its construction-start evidence, or racing to be in service by the end of 2027. The quality of beginning-of-construction documentation — physical work records or the five percent cost safe harbor — has become the most valuable file in the data room, all the more so after a federal court vacated the IRS notice that had restricted the five percent route, restoring it weeks before the deadline.

Everything else — storage, nuclear, geothermal, hydropower, fuel cells — keeps the original phase-down: full value for construction starts through 2033, then 75 percent (2034), 50 percent (2035), zero after.

Bonus Credits: The Path to 50 Percent

A well-sited, well-sourced storage project stacks to 50 percent of eligible basis. The domestic content and FEOC tests run on different rules but overlap heavily in practice: United States cell supply typically clears both, which is why cell origin has become the central procurement decision of 2026-vintage projects.

The FEOC Overlay

Facilities and storage beginning construction after December 31, 2025 must clear the material-assistance cost ratio: total direct costs, less costs attributable to prohibited foreign entities, divided by total direct costs. The minimum for storage is 55 percent in 2026, stepping to 75 percent by 2030; for generation facilities, 40 percent rising to 60. Steel and iron are excluded from the computation, and Notice 2026-15 supplies interim safe harbors keyed to the domestic content tables, with supplier certifications carrying penalties of perjury.

Two further rules complete the regime: prohibited foreign entities cannot claim the credits at all from tax years beginning after July 4, 2025, and payments conferring effective control to a specified foreign entity within ten years of a 48E facility entering service trigger one-hundred-percent recapture — a decade-long counterparty screen that most owners have not yet operationalised.

What This Means in Practice

• Storage owners: the runway is long but the content test is live now — 2025-vintage construction starts escape it entirely, which makes begin-construction evidence for anything already procured the highest-value file to close.
• Wind and solar owners: audit the July 4, 2026 grandfathering position now, not at diligence — continuity requirements still apply through completion.
• Credit sellers: 6418 buyers bear recapture and the excessive-transfer penalty, so substantiation quality prices the trade.
• Public and co-op owners: elective pay survives, but 2026-vintage projects over 1 MW need domestic content or an exception to keep it.

Stacking With Clean Fuel Programmes

A 48E-credited asset keeps earning after the capital credit lands. Storage and charging infrastructure dispensing electricity to vehicles generates clean fuel standard credits — California, Oregon and Washington LCFS credits in the United States, and CFR Compliance Category 3 credits in Canada for cross-border operators — on every megawatt-hour, year after year. Renewable generation sells RECs alongside the federal credit, and power supplied to electrolysers under compliant accounting is what moves a hydrogen offtaker up the 45V tiers.

The capital credit pays once at commissioning; the fuel programmes pay on throughput for the asset’s life. Deployment planning that treats siting and offtake as tax strategy — not just interconnection strategy — routinely doubles the support stack on the same steel.