Pump Energy Index (PEI) Explained

Engineering-Led Pump Selection · Watermain Supply · Houston, TX

Pump Energy Index (PEI) Explained

PEI is the U.S. Department of Energy's yardstick for the energy performance of commercial and industrial clean-water pumps. This guide shows how the number is built, how to read it, which pumps must carry one, and how to put the right PEI on a submittal when an engineer's spec calls for it.

1.00Federal maximum PEI
LowerIs better
25 GPM+BEP flow to be in scope
Jan 27, 2020Applies by manufacture date

Who this is for: engineers writing pump specs, contractors answering a submittal comment, and owners of data centers, hospitals, high-rises and water systems who want to know what a PEI number on a nameplate is really telling them.

We supply PEI-rated vertical multistage pumps, end-suction pumps and variable-speed booster systems, and we size them the engineering way: duty point first, efficiency rating second. Call 1-888.510.4036 with your spec section and we will match the rating it asks for. All products are genuine, factory-new equipment in original manufacturer packaging, sold and supported by Watermain Supply, an independent industrial supplier.

The Short Version

  1. PEI = the pump's energy rating ÷ the rating of a pump that just meets the federal minimum. 1.00 is the legal ceiling for covered pumps; lower is better.
  2. Two flavors. PEICL (constant load) rates a bare pump or a pump with a motor. PEIVL (variable load) rates a pump sold by its manufacturer with a motor and speed control.
  3. Both divide by the same constant-speed reference, which is why packaged variable-speed pumps post numbers like 0.38–0.45.
  4. Five pump families are regulated: end suction close-coupled, end suction frame-mounted, in-line, vertical multistage (RSV) and submersible turbine up to 6 in bowls — within set flow, head, power and speed limits.
  5. Everything else is rated another way or sits outside the rule: circulators get CEI, pool pumps get WEF, and fire, self-priming, prime-assist and solids-handling pumps carry no PEI.
  6. PEI compares pumps; your duty point picks the pump. A right-sized pump beats an oversized low-PEI pump on the electric bill every time.

What Exactly Is PEI?

A standardized energy comparison against a federal reference pump, calculated over several flow points instead of one.

The Pump Energy Index comes from the DOE energy conservation standard for commercial and industrial pumps (10 CFR 431, Subpart Y), which took effect for covered pumps manufactured starting January 27, 2020. It is not the hydraulic efficiency of the pump at its best point. DOE measures the input power the pump needs at prescribed load points, weights them into a Pump Energy Rating (PER), and divides that by the rating of a hypothetical pump of the same size and type that would just meet the federal minimum.

PEI = PER ÷ PERSTD PER = energy rating of the rated pump (hp)  |  PERSTD = energy rating of the minimally compliant reference pump (hp)

Both terms are in horsepower, so PEI is a dimensionless ratio, rounded to two decimals. A PEI of 0.75 means the pump's rated input energy is 75 percent of the reference pump's — 25 percent less power at the DOE load points.

Common mistakePEI 0.75 describes energy relative to a reference, while hydraulic efficiency (for example, 72 percent at BEP) describes how much shaft power becomes water power. They are two different numbers, and a pump sheet may show both.

How PER and PERSTD Are Built

The rated pump is measured; the reference pump is calculated from the rated pump's own hydraulics.

The rated pump: PERCL

For constant-load ratings, DOE takes the driver input power at three flow points and weights them equally:

Load point (percent of BEP flow) Weight in PERCL Why it is there
75 percent 1/3 Pumps spend real hours throttled back below BEP
100 percent 1/3 The best efficiency point itself
110 percent 1/3 Pumps are often selected slightly to the right of BEP

The reference pump: PERSTD

DOE keeps no physical “standard pump”. PERSTD is calculated from the tested pump's BEP flow, BEP head, nominal speed (1800 or 3600 rpm class), stage count and specific speed. Those feed DOE's minimum-efficiency equation, tuned for each pump family by a constant called the C-value. The reference pump is always paired with a minimum-efficiency motor (the federal NEMA Design B minimum, or a default submersible motor efficiency for ST pumps) and runs at constant speed.

DOE family Description C-value, 1800 rpm C-value, 3600 rpm
ESCC End suction close-coupled 128.47 130.42
ESFM End suction frame-mounted / own bearings 128.85 130.99
IL In-line 129.30 133.84
RSV Radially split, multistage, vertical, in-line diffuser casing 129.63 133.20
ST Submersible turbine 138.78 134.85

Source: 10 CFR 431.465, table in paragraph (b)(4), as published in the eCFR in September 2026. The same C-value applies to the CL and VL classes of each family. A C-value is an equation constant, not an efficiency percentage.

The detail most guides missPEIVL is divided by the same constant-speed PERSTD as PEICL. The reference never gets a drive. That is exactly how DOE gives credit for variable speed, and it is why a pump, motor and drive package can rate 0.40 while the same pump on a constant-speed motor rates 0.90.
EVERY PEI DIVIDES BY THE SAME REFERENCE Federal limit 1.00 Reference pump: constant speed, minimum-efficiency motor (PER STD) 1.00 Pump + premium motor, constant speed (PEI CL) 0.85 Pump + motor + drive, sold as one package (PEI VL) 0.40 Illustrative values. For a real example, Grundfos publishes PEI VL 0.38–0.45 for the CRE pumps in its Hydro Multi-E boosters.

Bar length is proportional to the energy rating at the DOE load points.

How a Pump Is Actually Tested

DOE's uniform test method is built on Hydraulic Institute HI 40.6-2021, with DOE's own additions.

On the test stand

The pump runs at nominal speed on a calibrated stand. Flow is throttled through at least seven points — 40, 60, 75, 90, 100, 110 and 120 percent of expected BEP flow — while the lab records flow, suction and discharge head, speed, and input power or torque.

The efficiency curve built from those points locates the best efficiency point (BEP), and the load points for PER are set from it. All data is normalized to 1800 or 3600 rpm.

Rules that shape the number

  • Stages: RSV pumps are rated at 3 stages and ST pumps at 9 (or the closest the model offers). Every stage count of a bare RSV or ST pump shares one rating.
  • Basic model: impeller trims of one pump may be grouped, so PEI belongs to a basic model, not to each catalog SKU.
  • Speed class: a pump designed for 2,880–4,320 rpm is a 3600 rpm pump; 1,440–2,160 rpm is 1800.
  • Sampling: the certified PEI must be at least the higher of the sample mean and an upper 95 percent confidence limit, so it reflects production pumps, not the best one off the line.

Who does it: the manufacturer. It may test in its own qualified lab or an outside lab, use the calculation-based methods written into the test procedure for pumps sold with regulated motors, or use an Alternative Efficiency Determination Method (AEDM) validated under 10 CFR 429.70. The manufacturer certifies the result to DOE through the Compliance Certification Management System (CCMS) and answers for it; DOE holds enforcement authority and can pull units for verification testing.

RuleA formal PEI comes from the DOE procedure and the manufacturer's certification. Reading efficiency off a catalog curve gives a good estimate of hydraulics, and the certified PEI comes from the manufacturer.

PEICL vs PEIVL

Which PEI a pump carries is set by how the manufacturer sells it, not by how it is installed.

PEICL — constant load

Applies to: bare pumps, and pumps sold with a motor but no speed control (an on/off switch or float still counts as constant load).

Load points: 75, 100 and 110 percent of BEP flow at full speed, weighted 1/3 each.

Bare pumps are rated with a default minimum-efficiency motor, so the number isolates the hydraulics. A pump sold with a premium-efficiency motor earns a lower PEICL than the same pump bare.

PEIVL — variable load

Applies to: pumps sold by the manufacturer with a motor and a continuous or non-continuous speed control, and pumps with inverter-only synchronous motors.

Load points: 25, 50, 75 and 100 percent of BEP flow, weighted 1/4 each, with speed reduced along a DOE reference system curve.

Examples: Grundfos CRE pumps with the drive built into the motor, Grundfos CRFlex.

Why variable speed scores so well

Centrifugal pumps follow the affinity laws: flow changes with speed, head with speed squared and power with speed cubed. At 80 percent speed a pump needs about 0.8 × 0.8 × 0.8 = 0.512, or roughly half, of its full-speed power under ideal conditions. A drive that slows the pump when demand drops, instead of burning the excess head across a throttled valve, collects that saving at every part-load hour.

Booster cautionThe same law says head falls with speed squared: at 80 percent speed a pump makes about 64 percent of its full-speed head. A booster holding a fixed pressure at the top of a building has to keep making that pressure at low flow, so it slows less than the DOE reference system curve assumes. Its field savings are real and usually smaller than its PEIVL implies. We size boosters on the duty point for exactly this reason.
Field-added drivesA constant-speed pump fitted with a VFD on site keeps the PEICL on its nameplate; the savings are real, and the DOE rating stays with the configuration the manufacturer shipped. Where a spec calls for PEIVL, either buy the manufacturer's packaged pump, motor and drive, or ask whether the engineer accepts a Hydraulic Institute Energy Rating certificate, which HI created for distributor-added motors and drives on pumps listed in its database.

How to Read a PEI Number

Compare CL with CL and VL with VL, within the same pump family and speed class.

PEI What it means
Above 1.00 Not permitted for a covered pump manufactured on or after January 27, 2020.
1.00 Exactly at the federal limit: the rated pump uses as much energy as the minimally compliant reference.
0.90 About 10 percent less energy than the reference at the DOE load points.
0.75 About 25 percent less energy than the reference.
0.38–0.45 What Grundfos publishes for its CRE pumps in Hydro Multi-E and for CRFlex: packaged pump, motor and drive, rated PEIVL. Roughly 55–62 percent below the constant-speed reference.
Worked example 1 — the ratioA pump's PER is 14.2 hp and its PERSTD is 17.5 hp. PEI = 14.2 ÷ 17.5 = 0.811, reported as 0.81: about 19 percent less energy than the reference pump at the DOE load points.
Worked example 2 — what 0.10 is worthTwo constant-speed pumps for the same duty, PERSTD = 20 hp. PEICL 0.90 gives 18.0 hp; 0.80 gives 16.0 hp. The 2.0 hp gap is 1.49 kW. Over 6,000 hours a year that is about 8,950 kWh, or about $895 a year at an assumed $0.10 per kWh.

PEI rates the pump; your system sets the bill

Actual consumption depends on the real duty point, the system curve, operating hours, sizing, motor efficiency, controls and how many pumps run in parallel. A correctly sized pump with a PEI of 0.90 routinely uses less power than an oversized pump rated 0.75 that spends its life throttled far left of BEP. Use PEI to choose between pumps that already fit the duty; use the pump curve to decide which ones fit.

Does Every Pump Need a PEI?

PEI covers five pump families inside set limits. Other pumps carry a different DOE metric or sit outside the rule, and a pump without a PEI can be perfectly efficient.

Pump group DOE status (as of Sept 2026) Examples on our site
ESCC, ESFM, IL, RSV, ST (inside the limits below) Must be rated and certified at PEICL or PEIVL of 1.00 or less; manufactured on or after Jan 27, 2020 Grundfos CR 10 and CRE 10; Franklin 6VR, 10VRL and larger VR pumps; Franklin AG, HC and XS close-coupled pumps
Horizontal multistage (RSHES, RSHIL), small vertical in-line under 1 hp (SVIL), vertical turbine to 6 in bowls (VT) Covered by the DOE test procedure since 2023, with no efficiency standard yet. Any efficiency claim must come from the DOE test Grundfos CME in Hydro Multi-B systems
Circulator pumps Own index, CEI; federal limit of 1.00 applies from May 22, 2028 Hot-water and hydronic circulators
Dedicated-purpose pool pumps Own metric, WEF; standard since July 19, 2021 —
Fire, self-priming, prime-assist, magnet-driven, nuclear and listed military pumps Excluded from the PEI standard by name Franklin FBSE self-priming pumps; vacuum-assisted dewatering pumps
Pumps under 25 GPM at BEP Outside the standard Grundfos CR 3 and CR 5; Franklin 1VR, 3VR, 1VRL, 3VRL and 6VRL; most residential jet and booster pumps
Sewage, effluent, grinder and other solids-handling pumps Outside the standard: DOE's “clean water pump” limits solids to 0.016 lb/ft³ Sump, sewage and effluent lines

The limits that put a pump inside the standard

  • BEP flow of 25 GPM or more at full impeller diameter.
  • Head of 459 ft or less at BEP, at full impeller diameter and the stage count required for testing.
  • Shaft input power of 1 to 200 hp at BEP (part of each family's definition).
  • Design temperature range of 14 to 248 °F.
  • Designed for a 2- or 4-pole induction motor, or a non-induction motor whose range includes 2,880–4,320 or 1,440–2,160 rpm, with the motor and impeller turning at the same speed.
  • ST pumps: bowl diameter of 6 in or smaller. ESCC and ESFM pumps: specific speed of 5,000 or less (U.S. units).
  • Manufacture date: the standard applies to pumps built on or after January 27, 2020. Earlier inventory may still be sold and installed.
Quick ruleAnswer four questions: Is it one of the five families? Is it a clean-water pump? Is it inside the flow, head, power and speed limits? Is it free of the named exclusions? Four yeses mean the pump must carry a certified PEI. Our own catalog shows the flow line clearly: Franklin's 3VR has a nominal BEP of 16 GPM and carries no PEI, while its 6VR, at 32 GPM, is in scope.

Where PEI Shows Up — and How to Verify It

A covered pump carries its rating in three places you can check.

1. The nameplate

Federal labeling rules (10 CFR 431.466) require the permanent nameplate to show PEICL or PEIVL, the bare pump model number and the impeller diameter (or a space to write it in).

2. The catalog

The same information must appear on each catalog page that lists the pump and in the manufacturer's other marketing materials. If a catalog page for a covered pump has no PEI, ask why.

3. DOE's database

Certified basic models are published in DOE's public Compliance Certification Database. Many are also listed in the Hydraulic Institute Energy Rating (ER) database at er.pumps.org, which rebate programs use.

What to request for a covered pump

  • Exact model and DOE basic model
  • PEICL or PEIVL, and which configuration it applies to (bare, with motor, with motor and drive)
  • DOE equipment class and nominal speed (for example RSV.3600.VL)
  • BEP flow, BEP head, full impeller diameter and stage count
  • Whether the rating came from testing, the DOE calculation method or an AEDM
  • The DOE certification listing, and the test report when the project's due diligence requires it
Two different claims“This pump was tested on a test stand” describes one pump. “This basic model is rated and certified to DOE under 10 CFR 431 and 429” describes every pump of that model. Specs and rebates need the second. For DOE purposes an importer is treated as the manufacturer, so an imported pump sold into a covered class carries the same certification duty.

Where PEI Decides the Order

On these projects, the PEI on the submittal is part of what gets approved.

Data centers

Cooling-water makeup, domestic boosting and process water run around the clock, so every point of PEI compounds. Owners reporting energy intensity want documented numbers, and redundancy (duplex and triplex) multiplies the pumps on the schedule.

Hospitals and healthcare

Continuous duty, strict redundancy and long equipment lives. Healthcare specs regularly call for variable-speed boosters on the building automation system; a certified PEIVL answers the efficiency line of that spec.

High-rise residential, hotels and offices

ASHRAE 90.1 section 10.4.2 requires service-water booster systems to vary speed or stage pumps from pressure sensors, avoid pressure-reducing the whole booster output, and shut off at no flow. PEIVL packages fit that requirement naturally.

Commercial HVAC

Chilled water, condenser water and heating water commonly run on end-suction and in-line pumps, two of the five regulated families. Energy-modeled projects pull pump input power straight from the rating.

Municipal and water systems

Booster stations, treatment-plant process pumps and 6 in submersible well pumps (the ST family) run long hours, where a lower PEI shortens the energy payback on a better pump.

Irrigation, agriculture and campuses

End-suction and submersible pumps with high annual hours, where every kWh is paid at the meter. Universities and public owners can write efficiency floors into their own pump specs.

How the number turns into money

  • Spec compliance. Specs can read like “pumps shall have a PEIVL of 0.50 or lower” or “listed in the HI Energy Rating database”. A submittal without the number comes back.
  • Rebates. Utility and government programs have used PEI and the HI Energy Rating as qualifying criteria. The HI ER is calculated directly from PEI and expresses percent power savings against a baseline for each pump class. Programs change often, so check your utility before you count on one.
  • Life-cycle cost. Energy is typically the largest cost of owning a pump that runs long hours; the purchase price is small by comparison.
When PEI is the wrong tiebreakerIf a pump only runs a few hundred hours a year (a transfer or standby duty), the payback on a lower PEI can be longer than the pump's life. And on a residential booster under 25 GPM there is no PEI to compare at all. We will tell you when a lower-PEI package is worth it and when it is not.

PEI-Rated Commercial Pumps We Supply

Variable-speed boosters and vertical multistage pumps from Grundfos, Franklin Electric and A.Y. McDonald, with the rating status of each line.

Grundfos Hydro Multi-E CRE booster system with PEI-rated variable-speed pumps

Grundfos Hydro Multi-E

RSV.3600.VL · PEIVL 0.38–0.45 per pump

Duplex and triplex boosters built on CRE 10, 15 and 20 pumps, each with its drive integrated in the motor. Grundfos publishes the PEIVL of every pump size and voltage, and states the skid itself carries no separate PEI: the rating belongs to each pump.

Best for: data centers, hospitals and offices where the spec asks for a documented PEIVL and BMS connectivity.

View Hydro Multi-E Duplex
Franklin Electric VR SpecPAK duplex vertical multistage booster system

Franklin Electric VR and VR SpecPAK

RSV family · 1800 and 3600 rpm

VR vertical multistage pumps from 30 to 450 GPM nominal BEP sit inside the PEI standard, and the VR SpecPAK puts two to four of them on Cerus X-Drive VFDs under one PLC for large commercial and municipal boosting. The PEI for the exact VR build goes on the submittal.

Best for: large buildings and data centers needing high flow on 460V three-phase.

View VR SpecPAK Duplex
A.Y. McDonald DuraMAC IQ1000 duplex vertical multistage variable speed booster pump

A.Y. McDonald DuraMAC IQ1000

Vertical multistage · Yaskawa iQpump drives

Simplex, duplex and triplex variable-speed boosters on stainless bases with lead-lag alternation, carrying up to 420 GPM in triplex form. A.Y. McDonald's price list does not publish a PEI for the skids; when a spec needs one, we get the pump-level rating from the factory with the submittal. Watermain Supply is an Authorized Stocking A.Y. McDonald and Baker Water Systems Distributor.

Best for: mid-size commercial and multifamily boosting where fast delivery and a proven drive matter most.

View DuraMAC IQ1000 Duplex
Line DOE family Rating Published PEI / status
Grundfos Hydro Multi-E (CRE 10, 15, 20) RSV, 3600 PEIVL per pump 0.38–0.45 (Data Booklet 99347082)
Grundfos CRE 10, CRIE 10, CRNE 10 RSV, 3600 PEIVL In scope; rating on nameplate and submittal
Grundfos CR 10, CRI 10, CRN 10 with motor RSV, 3600 PEICL In scope; rating on nameplate and submittal
Grundfos CRFlex RSV PEIVL 0.41–0.45 (CRF 10 and 15)
Grundfos CR 3 and CR 5 families, Hydro Multi-E CRE 3 and 5 RSV — Under 25 GPM at BEP: outside the standard
Grundfos Hydro Multi-B (CME) Horizontal multistage — DOE test procedure only; no standard yet
Franklin 6VR, 10VR to 95VR, 10VRL to 95VRL RSV, 3600 / 1800 PEICL (with motor) In scope; rating on submittal
Franklin 1VR, 3VR, 1VRL, 3VRL, 6VRL RSV — Under 25 GPM at BEP: outside the standard
Franklin VR SpecPAK RSV pumps on X-Drive VFDs Per pump Rating on submittal
Franklin AG, HC, XS close-coupled ESCC PEICL Franklin states its single-stage centrifugals are DOE compliant
A.Y. McDonald DuraMAC IQ1000 and Micro Vertical multistage skid Per pump Pump-level rating from the factory on request

Published values are taken from our product listings and the manufacturers' literature cited on them. PEI is a generalized rating and does not predict efficiency in a specific application; confirm the rating for the exact build on the manufacturer's submittal.

Looking beyond PEI? Compare every commercial booster we carry on the booster pumps collection, or read how to select a commercial variable speed booster pump.

Quick Reference

The numbers that decide whether a pump needs a PEI, on one screen.

≤ 1.00Maximum PEICL or PEIVL
25 GPMMinimum BEP flow in scope
459 ftMaximum BEP head in scope
1–200 hpShaft input power at BEP
14–248 °FDesign temperature range
6 inLargest ST bowl in scope
3 / 9Test stages, RSV / ST
Jan 27, 2020Manufacture-date compliance

Glossary

BEP — best efficiency point: the flow and head where the pump is most efficient.

Bare pump — the pump without motor, drive or controls.

PER — Pump Energy Rating: weighted input power at the DOE load points, in hp.

PERSTD — the PER of a minimally compliant, constant-speed reference pump.

C-value — DOE constant that sets the minimum efficiency for each family and speed.

Specific speed — a number describing impeller geometry from speed, flow and head per stage.

Basic model — a group of pumps with essentially identical energy characteristics, rated together.

Continuous control — a drive that varies speed smoothly with demand, such as a VFD.

AEDM — Alternative Efficiency Determination Method: a validated model used in place of testing.

CCMS — DOE's Compliance Certification Management System for certification reports.

HI ER — Hydraulic Institute Energy Rating, calculated from PEI and used by rebate programs.

CEI / WEF — DOE's separate indexes for circulator pumps and pool pumps.

Regulatory references

10 CFR Part 431, Subpart Y (Pumps): §431.462 definitions, §431.464 test procedure, §431.465 standards and C-values, §431.466 labeling, and Appendix A (uniform test method, incorporating HI 40.6-2021). 10 CFR §429.59 (sampling and certification) and §429.70 (AEDMs). ASHRAE 90.1 section 10.4.2 (service water pressure booster systems). Regulations change; this page reflects the eCFR as published in September 2026.

Frequently Asked Questions

The questions engineers, contractors and owners ask us about PEI.

Is a lower PEI always better?

Yes, for two pumps that both fit the duty and carry the same kind of rating. Compare PEICL with PEICL and PEIVL with PEIVL, in the same pump family and speed class. Between a right-sized pump and an oversized one, the right-sized pump wins on energy regardless of PEI.

Does a PEI of 0.75 mean the pump is 75 percent efficient?

PEI 0.75 means the pump's rated input energy is 75 percent of the minimally compliant reference pump's at the DOE load points. Hydraulic efficiency is a separate figure, usually shown as a percentage at BEP.

Does every pump need a PEI?

Only clean-water pumps in five DOE families (end suction close-coupled, end suction frame-mounted, in-line, vertical multistage and submersible turbine up to 6 in bowls) with a BEP of 25 GPM or more, head up to 459 ft, 1 to 200 hp, and built on or after January 27, 2020. Circulators use CEI, pool pumps use WEF, and fire, self-priming, prime-assist and solids-handling pumps carry no PEI.

Why are PEIVL numbers so much lower than PEICL?

Both are divided by the same constant-speed reference pump with a minimum-efficiency motor. A variable-load package is rated at 25, 50, 75 and 100 percent of BEP flow with speed reduced, so its weighted input power is far below the constant-speed reference. That is how DOE credits variable speed.

If I add a VFD to a constant-speed pump, does its PEI change?

The nameplate keeps the PEICL the manufacturer certified, because the rating follows the configuration as shipped. The energy savings are still real. If a spec requires PEIVL, use a manufacturer-packaged pump, motor and drive, or ask whether the engineer accepts a Hydraulic Institute Energy Rating certificate for the added drive.

Does a packaged booster system have one PEI?

The rating belongs to each pump. Grundfos, for example, publishes PEIVL for each CRE pump in its Hydro Multi-E boosters and states the skid carries no separate PEI.

Can a pump without a PEI still be installed?

Yes. Pumps outside the covered families or limits carry no PEI, and covered pumps manufactured before January 27, 2020 may still be sold and installed. A missing PEI says nothing about whether a pump is efficient.

Who calculates and certifies PEI?

The manufacturer, using the DOE test procedure (built on HI 40.6-2021), the DOE calculation methods or a validated AEDM, and then certifies each basic model to DOE. For DOE purposes an importer is treated as the manufacturer.

Where do I find a pump's PEI?

On the permanent nameplate, on each catalog page that lists the pump, in DOE's public Compliance Certification Database and, for many models, in the Hydraulic Institute Energy Rating database. For any pump we supply, ask us and we will put it on the submittal.

Can PEI help a project qualify for a rebate?

Often. Utility and government programs have used PEI and the Hydraulic Institute Energy Rating, which is calculated from PEI, as qualifying criteria. Programs change, so confirm the current terms with your utility before counting on one.

Check Yourself

Four situations from real submittals. Decide, then open the answer.

1. A spec asks for the PEI of a Grundfos CR 5 with a BEP near 20 GPM. What do you submit?

A note that the pump is outside the DOE standard: BEP flow is under 25 GPM, so no PEI exists. Submit the curve and motor efficiency instead, or step up to a CR 10 if the engineer needs a rated pump.

2. Pump A is rated PEICL 0.88 and package B is rated PEIVL 0.44. Does B use half the energy of A?

Only under DOE's assumed variable-load profile. The two ratings use different load points, so the real saving depends on how the system actually runs. A booster holding fixed pressure saves less than a circulating system with a falling system curve.

3. A self-priming centrifugal pump has no PEI on its nameplate. Is that a compliance problem?

No. Self-priming pumps are excluded from the PEI standard by name, along with fire, prime-assist, magnet-driven, nuclear and listed military pumps.

4. The spec reads “PEIVL 0.50 or lower”. Does a bare pump with a field-installed VFD comply?

Its nameplate still reads PEICL. Meet the spec with a manufacturer-packaged pump, motor and drive (a Grundfos CRE, for example), or ask the engineer in writing whether a Hydraulic Institute Energy Rating certificate for the added drive is acceptable.

Need the Right PEI on Your Submittal?

Send the spec section, the duty point and the building. We will match the rating it asks for, size the pump to the real duty and return a manufacturer submittal.

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Watermain Supply · Houston, Texas · 1-888.510.4036 · sales@watermainsupply.com · Free shipping on orders of $500 and up
This guide is an educational summary of the U.S. Department of Energy pump regulations (10 CFR Parts 429 and 431) as published in September 2026 and is not a substitute for the regulation, formal certification or engineering analysis. Product data is taken from Grundfos, Franklin Electric and A.Y. McDonald literature and is subject to change by the manufacturer; confirm the rating for the exact build on the manufacturer's submittal.
Grundfos, CR, CRE, CRFlex, Hydro Multi-E and Hydro Multi-B are trademarks of Grundfos Holding A/S; Franklin Electric, VR SpecPAK and Cerus X-Drive are trademarks of Franklin Electric Co., Inc.; A.Y. McDonald and DuraMAC are trademarks of A.Y. McDonald Mfg. Co.; Baker Water Systems, Yaskawa, iQpump, ASHRAE and Hydraulic Institute are trademarks of their respective owners. All are used here for product identification only.
Watermain Supply is a DBA of E4 Industrial LLC, an independent industrial supplier based in Houston, Texas.