In the June issue the Enterprise covered basics of energy and power considerations for a new or retrofit plant project. This is a continuation of that discussion with energy consultant Ralph Russell. It focuses on transformer and right-of-way issues as well as power quality and power outage concerns.
Energy consultant Ralph Russell has worked with a variety of industries including forest products companies to save money on their power bills and improve plant efficiencies. Russell is currently president of eDiscoveri Energy and has contributed columns to this magazine in the past. Russell formerly worked as a key account manager for a major utility provider, and he knows the process of power management in and out. You can reach Russell at 804-291-7667 or email rwrussell2@eDiscoveri.com.
Pallet Enterprise: So one of the things that we’ve already talked about was the load that’s required and that you may have to have a different size transformer. What are some other transformer related issues to consider?
Ralph Russell: Well, the utility is going to need space to place this transformer. Is the customer prepared to provide that space? As far as size, I would put transformers in three categories. One is a pole-mounted transformer. That doesn’t require much space from the customer, other than the space for the pole and the line. Then you have something called a pad-mounted transformer, which is usually a small concrete type of pad, may be 6' x 6'. And the biggest option is a substation transformer. Now you’re getting into a graveled area with a fence around it, and these are oil-filled transformers, and so this space can be huge depending on the size of the transformer. In some cases, the utility may build a dike around the transformer in case the oil leaks.
Pallet Enterprise: What about right-of-way issues? How can these impact a project?
Ralph Russell: If power lines are not already up leading to a facility, you can have some issues getting the right-of-way for new lines. Whether it’s underground or overhead, if it’s on the customer’s property, the customer’s responsible for providing that land as a right-of-way. If you’re lucky, the power lines are going down the front of your property. No big deal. But it could be that it’s two doors down and they had to cross a neighbor’s property. And, the neighbor may say, “I don’t want it crossing.” So, if the right-of-way that they have to get is only to serve this individual customer, there may be a cost to get right-of-way from the neighbor. Or, it could be that the route goes over a marsh where an endangered salamander lives. Instead of going through that area, the Army Corps of Engineers requires you to go around, adding 10,000 feet to the journey.
Pallet Enterprise: So if you have an existing facility or you are building a plant in stages, there could be some transitional issues to consider when it comes to power needs. How do you typically handle those temporary power challenges?
Ralph Russell: Temporary power – each utility handles this differently. But what I’m most familiar with is unique construction power. In many cases it’s the electrical contractor that’s calling in for this service to power saws, drills and construction equipment. Sometimes this can be handled with just a basic generator. But in many instances, the power demand is greater than what a generator can provide. And that is when you would call in a utility for temporary power, especially if the demand is greater than what the existing facility can provide, or if power is needed in a separate location.
Pallet Enterprise: Some locations may not have the same power quality available as others. Please explain the factors to keep in mind when it comes to power quality requirements.
Ralph Russell: Okay, there are two concepts to remember here – reliability and power quality. Reliability refers to disturbances that last more than two minutes. Power quality is usually sub-cycle types of disturbances, sags, transients, surges that occur on a cyclical basis. However, reliability involves longer power disturbances, basically a power outage. With poor power quality your equipment is still running, but you get this little sag or surge or spike in the power, and it can wreak havoc with your electronic equipment.
If you have new equipment that can be impacted by the reliability of service or power quality, you should find out how many outages that circuit has had. If you detect a problem, you may be able to work with the utility to get some sort of external upgrade to mitigate the potential problem. For example, if you’re moving in and you checked the record and found that last year, there were 50 outages, not disturbances, but outages on that line, would you possibly consider moving someplace else? Or would you ask the utility to make upgrades and improve the reliability?
Pallet Enterprise: When it comes to outages like that, what are the typical reasons that you have outage?
Ralph Russell: If it isn’t related to the facility itself, typical reasons for outages include falling trees or limbs, animal interference, failure of equipment, etc. Storms can be a regular problem if power lines travel along routes with a lot of trees. Other considerations could be salt contamination or hurricane and wind damage if you are located near the coasts.
Pallet Enterprise: When it comes to designing the power system at a plant, how does metering come into play?
Ralph Russell: Will the metering be done on the primary of the transformer or will it be done for each building? I’ve seen this in the lumber industry where over the years they’ve expanded and added meters to new buildings. And now, you end up with five or more different bills on one piece of property.
Primary metering would be on the high voltage side of the transformer, and you would end up with one bill. Now this may be a cost that the customer might have to bear, but it could be worth it based on having one bill versus many bills. And then, totalized metering, same scenario, but what you do is aggregate those loads virtually. In other words, the utility reads each meter, and then combines them at their mainframe. Again, while it’s virtual, the utility may charge you for this service.
