EAc4 is where a lot of LEED v5 feasibility conversations stall. Not because the credit is conceptually hard, but because the point thresholds sit on three different denominators, and one of the paths to points is not a percentage at all.

This is a reference for how the credit is actually structured in BD+C v5, and where the estimate usually goes wrong before a design exists.

What the credit is worth

  • New Construction: 1 to 5 points
  • Core and Shell: 1 to 4 points total, with a readiness option worth 1 of those points

Three tiers can be combined. The tiers are ordered by how directly the project is responsible for the generation: on-site first, contracted new off-site second, unbundled certificates third.

One more stake in the ground: for LEED Platinum, v5 requires 100% of site energy (base building energy for Core and Shell) from some combination of the three tiers. EAc4 is not optional math for a Platinum target.

Tier 1: on-site generation

Generation the project is directly responsible for. The equipment can sit on the project site, on the campus the project belongs to, or at a qualifying social impact project where the system is donated and the recipient keeps the power. On-site is the common case, but the tier is defined by that responsibility, not by a technology list.

Percentage thresholds

  • New Construction, share of annual site energy: 5% / 10% / 20% / 35% for 1 to 4 points
  • Core and Shell, share of base building energy: 15% / 30% / 65% / 100% for 1 to 4 points

The fifth New Construction point sits above the tier tables: it requires 100% of annual site energy from Tier 1 and/or Tier 2 combined. Certificates cannot carry you there.

Note the denominator changes. New Construction is measured against annual site energy. Core and Shell is measured against base building energy, defined as the greater of the estimated site energy from base building meters or 25% of the total estimated building energy. That is usually the smaller number, so carrying an NC percentage into a CS project overstates the result.

The threshold that is not a percentage

For the first two points, the table offers a second way in. Instead of hitting the percentage, the project can install a minimum rated capacity:

  • A x 1 W/sf for the first point
  • A x 2 W/sf for two points

where A is the sum of the gross floor area of up to the three largest floors, not total gross floor area and not roof area.

The table says OR: percentage or capacity, whichever the project can document. That makes this a friendlier route than it first looks, especially early. Before there is a yield model, installed capacity is a number a design team can actually commit to. And on a tall building, A stops growing after the three largest floors while total energy keeps climbing, so the capacity route can be the realistic one.

The misread to avoid: this is not an extra hurdle stacked on top of the percentages. A summary that treats it as a mandatory capacity floor is describing a different credit.

Tier 2: new off-site renewable electricity

Off-site electricity from new generation assets. The usual instruments are a utility green tariff, a virtual PPA, or community solar, but the defining requirement is that the contract is tied to new generation:

  • Contracted to be operational within two years of building occupancy, or
  • Contracted no more than five years after the asset's commercial operations date

Thresholds:

  • New Construction: 20% / 40% / 60% / 80% for 1 to 4 points, plus the same combined 100% Tier 1 and/or Tier 2 level for the fifth point
  • Core and Shell: 35% / 70% / 100% / 200% for 1 to 4 points

The Core and Shell scale runs past 100 percent. That is intentional: because the CS denominator is base building energy, exceeding it is how a CS project reaches the top of the scale.

Contract length is 10 years, or prorated across 10 years for shorter contracts. A 5-year PPA is not disqualified, it just counts for less. Green-e certification enters Tier 2 only for bulk purchases that exceed 100% of annual electricity use, measured against base building electricity for Core and Shell.

Tier 3: energy attribute certificates

Unbundled RECs, GOs, or IRECs, or renewable fuels. Certification defines this tier: Green-e Energy for electricity, Green-e Renewable Fuels for fuels, or an equivalent program.

  • New Construction: 50% / 100% for 1 to 2 points
  • Core and Shell: 100% / 200% for 1 to 2 points

Tier 3 is capped at 2 points. Treating unbundled certificates as a way to buy the full credit does not work in v5.

The fine print that gets missed:

  • Contract length: 10 years, or prorated for shorter terms, same as Tier 2
  • Vintage: EACs must be generated no earlier than 18 months before the project's initial LEED application submission
  • All attributes must be retired on behalf of the project
  • Tier 2 and Tier 3 assets must be in the same country or region as the project

Core and Shell has a fourth path

If generation is not going to happen under the CS scope, there is a readiness option worth 1 point. It is more specific than leaving room on the roof:

  • A designated solar zone of at least 40% of gross roof area, made up of areas of at least 160 sf each with no dimension under 5 ft, kept clear of obstructions and shading
  • A structural wind and load analysis covering the mounting configurations named in the tenant guidelines
  • A reserved conduit pathway from the solar zone to the point of interconnection
  • A main electrical panel with at least a 200 A busbar and a reserved breaker space marked for future solar
  • Tenant guidelines documenting how a tenant would actually use all of it

The part that stalls a feasibility estimate

To put a number on Tier 1 you need an estimate of the solar and wind resource at the site. Before schematic design there is no array layout and no yield model, so the estimate has to come from climate data.

A typical-year file alone is not enough. TMY data is assembled to represent the long-term average, which is exactly why it says nothing about how far a weak year falls below it. A multi-year series is what lets you bracket the estimate instead of quoting one number.

NASA POWER is the practical answer for early screening. It is free, needs no API key, covers effectively any coordinate on earth, and returns more than ten years of both solar irradiance and wind speed. It is gridded data, roughly half-degree cells, so treat it as a regional screening proxy rather than a site measurement. Wind in particular reflects regional flow, not your rooftop. For a feasibility-stage EAc4 estimate, that is the right tool: honest brackets, not false precision.

A screening estimate should tell you which tier is realistic and roughly how many points are on the table. It should not pretend to be a yield study.

What trips people up

  • Reading the Tier 1 table as percentage-only and missing the capacity route to the first two points, or reading the capacity route as an extra requirement. The table says OR.
  • Using the New Construction denominator on a Core and Shell project
  • Treating the 10-year contract length as pass or fail. Shorter contracts prorate.
  • Assuming certificates can carry the credit. Tier 3 stops at 2 points.
  • Missing the 18-month EAC vintage window
  • Reading the Core and Shell 200 percent tier as a typo rather than a real step

Source: LEED v5 BD+C Reference Guide, February 2026 release, EAc4 at pages 108 to 112. Referenced standards include Green-e Energy, the RE100 Technical Criteria, and the GHG Protocol Scope 2 Guidance. Rating systems get addenda, so confirm the current text before you submit anything on the strength of a blog post.

If you want an early read on where a specific project lands, the free VERTIQ feasibility check runs the screening estimate across BD+C v4, v4.1, and v5, ID+C v4, v4.1, and v5, and O+M v5: https://vertiq.net/feasibility