Voltage sags and swells are short voltage disturbances. They reset controls, cost your motors torque, and drive out-of-warranty equipment repairs in commercial and industrial facilities.

This is Energy Decision #53 in the complete C&I energy management series by Daniel Burke. It's part of his mission to create the world's largest, free, high-trust energy resource library for commercial and industrial consumers.

In this episode, Daniel Burke covers:

- The thresholds: a voltage sag (dip) is 10 to 90 percent of nominal, a voltage swell is 110 percent or more, and how both differ from a transient voltage

- Undervoltage and overvoltage as the sustained versions of sags and swells

- Operational symptoms, including equipment resets, lighting flicker, and motor torque loss

- Common causes, from motor starts and loose connections to line-to-ground faults and transformer tap settings

- A four-step troubleshooting sequence using stakeholder interviews, thermal imaging, and multimeter checks

- How power analyzer data, combined with other checks, helps you tell whether a sag starts inside or outside your facility

- Mitigation by event type and cost: fixing internal causes, hardening sensitive controls, and saving a UPS for loads where the cost of a trip justifies it

- Why a periodic power quality study makes sense even when your plant shows no symptoms

If you've asked "why does my equipment keep resetting" or "how do I tell if a voltage problem is the utility or internal," this episode answers both.

Who this is for: plant managers, facility managers, and operations executives at manufacturing plants, hospitals, commercial buildings, and industrial facilities who are dealing with unexplained resets, motor faults, and early equipment failures.

If you're working out how to protect your equipment and operations from the cost of voltage sags and swells, this episode is built for you.

Read the full breakdown on Voltage Sags and Swells at tac-nrg.com

If you're an Indiana C&I operator actively evaluating this decision, get your free Energy Decision Blueprint at tac-nrg.com/blueprint.

Visit tac-nrg.com to access the entire Energy Answers resource library and the Energy Decision Blueprint for qualified Indiana C&I operators.

High-Efficiency Commercial HVAC Systems are the largest single energy end use in most commercial buildings. The Whole Building Design Guide estimates HVAC accounts for 39% of the energy used in U.S. commercial buildings, and most systems run at 50% or less of their capacity.

This is Energy Decision #52 in the complete C&I energy management series by Daniel Burke. It's part of his mission to create the world's largest, free, high-trust energy resource library for commercial and industrial consumers.

In this episode, Daniel Burke covers:

- HVAC part-load performance and why rated peak efficiency only applies at full load

- Oversized HVAC equipment and ASHRAE 90.1 safety factors as an upper limit

- Sizing replacements against measured BAS trend data and utility interval data

- Condensing boiler efficiency, return water temperature, and how it compares with firetube, watertube and cast iron boilers

- ENERGY STAR commercial boiler thermal efficiency and turndown ratio

- Chiller full-load kW per ton and IPLV/NPLV part-load ratings

- CAV with reheat compared with VAV systems

- DDC controls, variable speed drive chillers, water temperature reset and integrated chiller plant control

- HVAC commissioning and whole-building integration

- What payback estimates for whole-building design do and don't tell you about a single equipment replacement

Who this is for: facility managers, plant managers and operations and finance executives at office buildings, schools, hospitals, manufacturing facilities and municipal buildings who are paying to heat and cool with equipment sized for conditions that rarely occur.

If you're deciding which high-efficiency HVAC solutions to invest in, or asking whether your chiller is oversized, this episode is built for you.

Read the full breakdown on High-Efficiency Commercial HVAC Systems at tac-nrg.com

If you're an Indiana C&I operator actively evaluating this decision, get your free Energy Decision Blueprint at tac-nrg.com/blueprint.

Visit tac-nrg.com to access the entire Energy Answers resource library and the Energy Decision Blueprint for qualified Indiana C&I operators.

Energy Audits (ASHRAE Level 1, 2, 3) set how much engineering rigor you buy when you pay for an energy audit. Pick the wrong level and you either waste audit money or rest a capital project on a rough savings estimate.

This is Energy Decision #51 in the complete C&I energy management series by Daniel Burke. It's part of his mission to create the world's largest, free, high-trust energy resource library for commercial and industrial consumers.

In this episode, Daniel Burke covers:

- Why "energy audit" tells you nothing until a vendor names an ASHRAE level

- ASHRAE Standard 211 and the Procedures for Commercial Building Energy Audits

- The Preliminary Energy Use Analysis: utility bill analysis, EUI calculation, and energy benchmarking

- The Level 1 walk-through audit and rough order of magnitude estimates for energy efficiency measures (EEMs)

- The Level 2 energy survey and analysis: equipment inventory, energy balance, and M&V plan

- The Level 3 detailed survey, the Investment Grade Audit (IGA), and performance contracts

- The conflict of interest when the ESCO that writes the IGA also builds the project

- Right-sizing audit spend against the savings your EUI benchmark suggests

- Scoping an audit to support LEED O+M requirements

- Screening auditors for ASHRAE BEAP and BEMP credentials

What's the difference between ASHRAE Level 1, 2 and 3, and which energy audit do you need for your building? Daniel answers both.

Who this is for: Building owners, industrial facility managers, and property managers at commercial buildings, industrial facilities, K-12 schools, hospitals, and municipalities who need to scope an audit without overpaying or under-scoping a capital project.

If you're deciding which ASHRAE energy audit level fits your building's savings goals and your tolerance for error on a capital project, this episode is built for you.

Read the full breakdown on Energy Audits (ASHRAE Level 1, 2, 3) at tac-nrg.com

If you're an Indiana C&I operator actively evaluating this decision, get your free Energy Decision Blueprint at tac-nrg.com/blueprint.

Visit tac-nrg.com to access the entire Energy Answers resource library and the Energy Decision Blueprint for qualified Indiana C&I operators.