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Load Monitoring
What is Load Monitoring?
Electric load monitoring generates important data that can help to unravel
the mystery behind commercial facilities' energy usage characteristics. Let
Good Energy show you how to uncover real potential for energy cost savings.
Call toll free at (866) 955-2677 for a consultation, or read on for more information:
In a perfect world, every customer would use a constant amount of power
at all times of the day, every day of the year. This would make it easy
for the companies saddled with the responsibility of maintaining and
operating the electricity generation and distribution systems to keep
everything running smoothly, and at an economical price. Unfortunately
for everybody, the world doesn't work that way. People use more power
at peak hours during the day when they are operating power-hungry machines
under bright fluorescent lights in air-conditioned offices, than they use
at night when they are home in bed. This means that utility companies must
make allowances for mid-day peaks in power consumption as they provide for
the generation, transportation and distribution of power to customers in the city.
In a deregulated electricity supply market, there are theoretically numerous
merchant power companies with generation assets standing by to provide
consumers with the power they need to operate the homes and businesses at a
fair price. Consumers are theoretically able to negotiate with the merchant
power companies to agree to a price for power, which will be added to the
charges imposed by the incumbent transmission and distribution grid owners
to deliver power to the consumer. However, not all customers will be able
to get the same good deal as every other customer, economies of scale aside.
A Comparison of Energy Consumers
To better understand how customers with different power usage characteristics can
get vastly different power bills and bids for power supply in deregulated markets,
let's start with a comparison of two theoretical commercial consumers of power.
Customer "A",
(let's call her Alice), as illustrated by the graph at right, has a business
that uses power on a steady basis, all day long, every day of the year. Customer "B",
(let's call him Bob), has a business that uses, on average, an identical amount
of power as Alice, but his usage characteristics differ from those of Alice. Bob
turns off all of his power-hungry machines and electrical devices each evening,
then turns them back on again in the morning. Bob's business competes with that
of Alice, so to maintain the same level of production as Alice, Bob's machines
have to make up for lost time, so he uses much more power than Alice during peak
hours although he uses less power at night. Now, for argument's sake, let's
assume both these customers want to negotiate with owners of generation assets for
the electricity supply to their facilities.
Let's assume Alice's absolute peak demand for power is 1,000 kilowatts, (kW).
Thanks to her flat demand for power, this means she requires 8.76 million kilowatt-hours
(kWh) to service her business. (8,760 total hours per year X 1,000 kW). Bob also uses
8.76 million kWh annually, but his peak demand is 1,500 kW. This means Bob has a
"load factor" of 66.7%, which is the relationship Bob's average demand for power,
(1,000 kW), bears to his peak demand for power, (1,500 kW). From a generator's
viewpoint, the lower a customer's load factor, the less desirable the customer will be.
To understand this, consider the viewpoint of one of the hypothetical companies
bidding to supply power to Bob and Alice. Let's assume a given generator's
maximum capacity is 1,500 kWh, which is equal to Bob's peak demand, but 50%
greater than Alice's peak demand. The generator is owned by a merchant power
company which has financing in place to cover the acquisition of the generation plant.
The merchant power company also employs staff to operate and maintain the plant, and
the company must purchase fuel, (natural gas, coal, oil, etc.), to produce power.
The fuel cost is a variable which will fluctuate in direct proportion to the amount
of power generated by the unit, while the financing costs and many of the operating
and maintenance costs are fixed. When offering a proposal to supply electricity to
Alice, the merchant power company knows that it will have 500kW left over to sell
to other consumers. Alice will get a much better offer than Bob. If the merchant
power company ends up doing a deal with Bob, it won't be able to sell power
to other consumers. Realistically, the merchant power company will need to capture
all of its operating expenses, financing costs and profit from Bob alone, while
Alice would only need to bear the brunt of 2/3 of those fixed costs. To put it
simply, the less-pronounced the customer's peak, and the higher the customer's
load factor, the better price the customer will achieve for power in any market,
deregulated or not. It makes economic sense for all consumers of power to improve
their load factors.
The same cost differential stemming from varying load factors applies to the cost
of transmission and distribution of power. Think of transmission lines as conduits
of a commodity. Similar to any conduit, electricity transmission and distribution
grids have a maximum capacity, just as you can only pipe so much data over
telecommunications lines or water through plumbing. As such, electrical transmission
and distribution capacity has value, and there is a cost associated with the "rental"
of space on the grid. Because Bob has a peak demand 50% higher than Alice, Bob has
to pay rent for 50% more capacity on the transmission and distribution grid. Bob's
cost for transmission could end up being far higher than Alice's in the event his
peak demand for power contributes to congestion over a grid. Congestion is a condition
that occurs when there is insufficient transmission capacity to supply all the demand
on a grid. This condition could lead to grid failures such as blackouts, and because
power could be drawn from adjacent grids at a premium, it would most certainly lead
to increased costs for consumers on the affected grid. There is also a variable used
in calculations of consumers' power costs known as "coincidence factor" which
is linked to that degree by which a given consumer's peak demand coincides with
the peaks of other consumers on a given system. The lower, (read: worse), a customer's
load factor, the more the coincidence factor could contribute to exceptionally high
costs for the delivery of power from the generator to the consumer, especially during
peak seasons. Most of the customers we encounter can make changes to their operating
methods or their facilities' systems to improve their load factors. Better load
factors lead to better prices for power.
Armed with the understanding that improving his facility's load factor will
save money and help his business compete with that of Alice, Bob might ask a consultant
what he can do to make a difference in his monthly power bills.
The
first step to answering this question is to gather information regarding current
conditions and practices at the customer's facility. I would ask Bob to send
me at least twelve months of his past (recent) electricity bills so I could get a
clear understanding of how he used power on a monthly and annual basis. Sometimes,
in conjunction with a customer interview, this stage of information-gathering can
reveal many things, and I might make some suggestions for possible energy saving
techniques. The suggestions might have to do with no-brainer equipment retrofits
including lighting system upgrades, but without a more detailed information-gathering
effort, I would be unable to make concrete and supportable recommendations which
would include energy upgrade payback schedules, etc.
Just as detailed inventory of energy-consuming equipment at Bob's facility
would help to refine my suggestions and pin down supportable estimates of cost
savings associated with the proposed changes, so too would a detailed analysis
of electricity usage patterns at Bob's facility help to pin down really
germane advice regarding how power usage characteristics could be modified,
(without impacting Bob's operation in any negative manner), to improve
his load factor. The vast majority of existing electricity meters installed
in commercial facilities record how much power was used in a given period,
(kWh), and what the peak demand was during that period, (kW). This information
is reported on a bill, but it is not really detailed enough to serve our purposes.
This is where load monitoring equipment makes its debut at Bob's facility.
I would rig a device to monitor kW usage in fifteen-minute intervals, while
recording ambient conditions such as temperature, major equipment duty cycles,
and other factors which might affect power usage characteristics. The load
monitoring equipment would be programmed to upload to our servers its recorded
data via one of Bob's existing phone lines at a pre-set evening hour while
Bob is asleep. Armed with this data, I might note by careful analysis in
conjunction with personnel interviews that all four air conditioning chillers
at Bob's facility were activated simultaneously each day when the temperature
in the facility reached 80 degrees. Bob might not have known that the simultaneous
activation of all four chillers actually contributed with the other systems in his
facility to set his peak at 1,500 kW each day. All Bob and I have to do is train
his staff or install an automatic control to stagger the starts of the chillers,
starting them one-at-a-time, in 15 to 20 minute intervals, and Presto! Bob's
peak demand might fall to 1,400 kW, and his load factor just improved from 66.7%
to 71.4%. Bob's cost for this modification alone is close zero.
There may be other quick fixes which have a negligible cost to Bob, but there will
most certainly be fixes such as a comprehensive lighting system retrofit, which
will have a substantial cost of implementation. In general, lighting retrofits
will pay back the investment in one to three years, (depending on kW rate and
hours of lighting system operation), and most business people are hard-pressed
to match that kind of return on capital, but as each subsequent modification of
facility systems is evaluated, we will certainly note a diminishing return on
capital and effort. For this reason, I always advise people like Bob to set out
a roadmap of expectations. How far do they want to drive, for example, for a
progressively better view, when the first couple of miles yield stunning vistas,
but then it could be many, many rest stops before the ultimate view is achieved?
Most people in Bob's shoes would save themselves a lot of time and frustration
if they would set out clear goals at the outset of any effort to improve energy
usage characteristics in a facility. For example, Bob might choose to draw the
line at any investment which does not yield a simple payback of four or five years.
Once this line is drawn, it becomes a quick and easy matter to use the data
collected by the load monitoring equipment over a period of several months to
calculate exactly how various energy upgrades and operating method modifications
will reduce Bob's total cost for power. The picture painted by the load
monitoring equipment will allow us to document in supportable figures exactly
what the savings will be, (assuming other variables are unchanged).
"Time of Use" Meter
Data produced by load monitoring equipment can help save customers money in
other ways too. For example, in many regulated and deregulated electricity
supply markets, consumers of power can request from their incumbent utility
company a "time of use" meter. This new meter would be installed at the
consumer's facility, replacing the older, "dumber" meter. The time of
use meter would record the same 15 minute interval data that our load monitoring
equipment would record, and, (now this is the key), the consumer would from
that point on be billed based upon their actual time of use. There are usually
different rates charged by utility companies for different times of day.
It's not hard to imagine that power will cost less at night when nobody
wants it, right? So, before the time of use meter was installed, the utility
company was making an assumption regarding how much power the customer was using
during "on-peak" hours, and how much power was being used during "off-peak"
hours, and chances are, their assumption was off, to the customer's benefit
or perhaps to their detriment as the case may be. Of course, certain customers
such as theaters, late-night restaurants, and possibly even hotels are most
certainly getting a bum deal by holding on to their "dumb" meters, but if a
customer doesn't know for certain that it would make economic sense to
make the switch, the customer had better not risk it. Once a customer switches,
he may not be permitted to go back to the dumb meter. At best, the customer
might be required to stick with the new meter for at least a year. The
accumulation and careful analysis of real-time load monitoring data can help
a consumer of power make the correct choice about switching to alternative
meters or rate classes, which could conceivably save a great amount of money.
These techniques apply to all sizes of electricity consumers, and the potential
for savings could be on par for large and small on a percentage basis. However,
if a sole homeowner could save 10% on her power costs, the savings would take
years to pay off her costs associated with the retainer of the consultant, the
installation of the load monitoring equipment and the completion of the analysis
and final report. If, on the other hand, an owner of a large midtown office building
could save 10% on his electricity costs, the cost of the consultant, analysis and
equipment becomes negligible. For this reason, we recommend load monitoring to
medium and large-size businesses.
Take the first step towards realizing energy cost savings at your facility by
contacting Good Energy today to schedule a consultation to review the
benefits of load monitoring equipment installation. Call us toll free at (866) 955-2677.
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