Two factories of the same size, in the same state, may have different risks of stopping due to lack of energy. One is located in a network section with few interruptions, and the other in a region with many occurrences, with a furnace that takes six hours to return to operation.
Assessing the operational energy risk is what turns this difference into an investment decision. Follow along to see how to measure this risk with public data and with three questions that the team itself answers.
Executive summary
- ANEEL publishes, by municipality, how many hours and how many times per year the average customer is without energy.
- The operational energy risk only becomes a number when this data meets the mapped critical load and the cost of downtime.
- Renting a generator pays off when the downtime costs more than the equipment’s monthly fee.
Index
- What constitutes the operational energy risk
- How to assess the operational energy risk in five steps
- When temporary energy is factored in
- Frequently asked questions about operational energy risk
- Conclusion
What constitutes the operational energy risk
The operational energy risk is formed by the intersection of three factors: the quality of supply in the region, what the operation cannot afford to lose, and the cost of each hour of downtime. Ignoring any of them distorts the calculation.
The quality of supply in your region
The quality of energy supply is measured and published: each distributor reports to ANEEL how many hours per year the average customer was without energy and how many times this happened.
These two supply quality indicators have their own name and rule: they are the DEC and FEC, defined in the Module 8 of PRODIST, which ANEEL calls Quality of Electricity Supply and publishes by municipality and by distributor.
These numbers vary greatly between cities served by the same distributor, making the indicator of the municipality itself the cheapest step in the entire evaluation, and almost no one checks it.
What your operation cannot tolerate
Critical load is everything that cannot be turned off without consequence, and the size of this list varies greatly from one place to another.
In a hospital, the critical load is evident and has its own standard, ABNT NBR 13534, while in industry it is usually a small and expensive subset, including server rooms, control systems, process cooling, and safety pumps.
The common mistake is to size contingency for the entire plant when the real risk is in 15% of it, or the opposite, to protect only the office and leave the process exposed.
How much does downtime cost
The cost of downtime is the number that decides everything else, and it adds up lost production, discarded raw materials, rework, idle labor, contractual penalties, and the cost of restarting the process.
Without this number, any discussion about energy investment becomes a personal preference. With it, the calculation solves itself: if downtime costs more than the monthly rental of a generator, the decision is made.
How to assess the energy risk of the operation in five steps
The guide below fits into an afternoon of work and does not require consulting.
1. Gather the history of your delivery point
The energy delivery point is where the distributor’s network ends and the company’s installation begins. Request the history of supply interruptions for the last 24 months for your consumer unit from the utility company.
This history shows frequency, duration, and cause, and is more accurate than the municipal average as it refers to your delivery point.
2. Compare with the city’s public indicator
With the history in hand, compare it with ANEEL’s indicator for the municipality. If your unit suffers more than the average, there is a local, branch, or network problem that can be addressed with the distributor.
If it suffers less, the risk is lower than internal perception suggests, and the investment can go elsewhere.
This comparison is the data that Tecnogera requests before sizing any rental because it separates the network problem, which is resolved with the distributor, from the risk that only a generator covers.
3. Map the critical load
List the equipment that cannot stop, with the power of each and the maximum interruption time they can withstand, as some tolerate minutes and others cannot tolerate even seconds.
This survey is faster when starting from the single-line diagram and the distribution panel, which the ABNT NBR 5410 requires to be documented in low voltage installation.
This map defines the type of protection: UPS for what cannot tolerate flickers, generator for what needs autonomy, both in series for what needs both.
4. Calculate the cost of downtime per area
Calculating by area, rather than the entire company, reveals where the money is, and there is often a big difference between the sector the management considers critical and what the spreadsheet shows as critical.
5. Define the level of electrical redundancy
Electrical redundancy is how much reserve the operation maintains, and the scale ranges from none, through a generator dedicated to critical load, to two independent power supply paths.
The generator’s operating regime is part of this choice and has its own classification in ABNT NBR ISO 8528, which separates emergency equipment from that which runs as the main source of operation.
Each step of this scale costs more and reduces more risk, and the right choice is the one that pays for itself with the cost of avoided downtime, not the most complete available.
When temporary power comes into play
Not every identified risk requires equipment purchase, and temporary power economically solves three situations that frequently arise in the assessment of the operation’s energy risk.
Seasonal risk
Seasonal risk appears when the operation has months of greater exposure, such as during heavy rain periods or production peaks, and renting during this window costs less than maintaining an idle asset all year.
Temporary risk
Temporary risk appears during construction, load expansion, or waiting for the increase in demand contracted with the distributor, and during this interval, the generator covers the operation without immobilizing capital.
Newly identified risk
The newly identified risk is what the assessment has just revealed, with high exposure and a definitive solution still months away from project and installation, and it is in this window that rental secures the operation.
Rental as a response to mapped risk
Tecnogera addresses these three situations with generators, chillers, platforms, and lighting towers from 28 units, with 24-hour on-call service, and sizes according to the critical load map and the ABNT NBR ISO 8528 regime, not the electricity bill.
Just inform the critical load, the deadline, and the city to receive a proposal.
Frequently asked questions about operational energy risk
Where can I check the outage history for my area?
The utility company serving the municipality publishes supply quality indicators and is required to provide the history of your consumer unit when requested by the account holder.
What is the difference between energy security and operational continuity?
Energy security refers to the ability of a country or region to ensure supply, while operational continuity refers to your company’s ability to continue operating when that supply fails.
Does every company need a generator?
Not every company needs a generator, as it is only justified for those with loads that cannot tolerate interruptions or where the cost of downtime exceeds the cost of protection, and the assessment exists to answer this with numbers.
Is a UPS enough?
It depends on the duration of the outage, as a UPS supports minutes and is used for safe shutdown or to cover the interval until the generator takes over. Hour-long outages require a generator.
How do I know the required power?
By adding the mapped critical load and considering the starting peak of motors, which is several times higher than the steady-state consumption. This is the calculation most often mistaken when done solely based on the electricity bill.
Is it better to rent or buy?
Purchasing makes sense in cases of permanent and high risk, while renting is better suited for seasonal, temporary, or newly identified risks, as well as situations where capital is better used in core activities.
Can a short outage damage equipment?
A short outage can cause more damage than a long one: fluctuations and automatic reactivation can harm electronics and motors when equipment is turned off and on without control.
What is a delivery point?
The delivery point is the boundary between the utility’s network and the customer’s installation, defining responsibility for each section and serving as a reference for the supply history.
How often should the assessment be redone?
The assessment should be redone once a year, and whenever there is an increase in load, a process change, or construction that alters the installation.
Is the evaluation used to negotiate with the distributor?
The evaluation is used for this and is one of its best uses, because a documented history of interruption is the argument that supports a request for network improvement or a change in the delivery point.
Conclusion
Operational energy risk is not a feeling, it’s a calculation, and it is calculated with the history of your delivery point, the critical load map, and the cost of downtime.
Once this calculation is done, the decision to protect, rent, or do nothing is no longer an opinion and becomes arithmetic, and it is with this in hand that Tecnogera sizes the rental, instead of selling more power as a precaution.
