NEW Power PE Exam Reference Handbook 2.1 Is Out! Here’s Everything That Changed (Plus a Few Error...

If you’re taking the Power PE exam in October 2026 or later, here’s a complete summary of every change (along with a few remaining errors) in the newly released NCEES® Power PE Reference Handbook 2.1.

This is the version of the Reference Handbook that will be available on your exam computer beginning with the October 2026 exam administration.

If you're taking the PE exam before October 2026, you can skip this post and refer to the one hour webinar recording on YouTube - Understanding the New 2025 Power PE Exam – Your Study Strategy Starts Here! for the previous updates instead.

1) Page v - Photovoltalic Systems now appears in the Table of Contents under: 2 GENERAL POWER ENGINEERING > 2.2 Applications > 2.27 Photovoltaic Systems p. 24:


2) Page 2 - candlepower (cp) conversion factor for lumens (lm) has been added to 1.2 Conversion Factor:


3) Page 19 - the formula for “plant factor” was renamed to “capacity factor” under 2.2.4 Demand Calculations. The word “produced” in the formula was changed to delivered:


4) Page 24 - Brand new section for photovoltaics added under 2.2.7 Photovoltaic (PV) Systems:

Includes four new formulas:

  • Photovoltaic system energy output (E)

  • Temperature-Corrected Maximum Power Point Voltage (Vmpp)

  • Temperature-Corrected Open-Circuit Voltage (Voc)

  • PV module fill factor (FF)

  • Includes a list of variable names.

This is aligned with the most recent exam specifications effective October 2025 that includes “photovoltaics [PV]” under 7. Electric Power Devices > D. Alternative power generation:

5) Page 62 did not correct the error from the previous Reference Handbook version 2.0.1 for the wye-grounded delta transformer connection zero sequence connection that is missing the variable "3Zn" that does correctly appears in Blackburn’s book for this circuit where these diagrams are cited from. This error is still present:

6) Page 70 did not correct the error from the previous Reference Handbook version 2.0.1 for the swing equation where "ws" is improperly named as the rotor synchronous speed (instead of the rotor angular velocity). This error is still present:

7) Miscellaneous: a lot of citations under formulas and images have been updated with no change to the formula or image.

Overall, updates are really minor and only represent a few new formulas for photovoltaics. Just watch out for the existing errors that were copied over from the pervious version.

All new photovoltaic formulas will be covered during this semester’s Class 10 - General Applications and Miscellaneous.

Hope this helps, and good luck to everyone studying for the Power PE exam! It's a tough exam, but well worth the effort.

Note: to download the updated Reference Handbook version 2.1:

  1. Log into your NCEES account at https://account.ncees.org/

  2. Useful Documents > View reference handbooks

  3. Click on: PE Electrical and Computer: Computer Engineering Reference Handbook 2.1 For October 2026 exam