Tag Archives: substation

07.02.20
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Vision Lights On! New Report Confirms Perche Creek Risk

Again we have been lucky to have a cool Spring. As hot weather arrives, though, it’s time for another reminder that our Council unnecessarily placed our electric service at risk when it voted to “pause” the transmission line planned for the Southwest, with no alternate plan in place.

Now yet another consultant has confirmed that yes, the Perche Creek substation is overloaded. In a presentation sent to the Integrated Electric Resource and Management Plan Task Force, the engineering firm assisting the task force (Siemens) confirms that the substation has exceeded its firm capacity (in fact is currently operating at 150% of firm capacity at peak temperatures) and that its associated feeders are overextended.

As we have pointed out before, this puts us at risk for serious outages. A failure at Perche Creek would affect everyone in Columbia. Note that both the McBaine Water Treatment Plant and the Gillespie Bridge Sewer Treatment Plant are served by the Perche Creek substation. Due to the failure to build the transmission line, these facilities are not backed up the way Water & Light had planned or would like to them to be.

The pandemic has given us ample illustration of the fact that when those in leadership positions ignore or deny latent but serious risks, the potential harm to citizens increases. When the line was paused it was on-time, on-budget, and fully funded. During the last five years, we have paid millions in increased rates (which were approved but not “paused” by the Council) without getting the promised return.

It is unlikely that at this point we will be able to fix our electric infrastructure without paying out millions more. We should, however, be able to get a full accounting of what the Council’s “pause” has cost us, put in the infrastructure needed to ensure the reliability of key services, and adopt procedures to ensure that the Council cannot in the future so easily and heedlessly derail key projects that the public has already approved and paid for.

08.21.18
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Keeping An Eye On Our Electric Service

We have previously discussed the Council’s ongoing failure to address the overloading of the substations that serve the South and Southwest and also affect power downtown. The overloading has only gotten worse. In 2015 the Perche Creek substation exceeded its loading goal by 22%. In 2017, that number was 29%. In July of 2018, it was 48%. Perche Creek was not the only substation to exceed its loading goals in July. Blue Ridge, Rebel Hill, and the Power Plant all exceeded 100% of their loading goals. Hinkson Creek was at 99%.

Electric systems must have reserve capacity for times of high loads and/or problems with the system such as those caused by storms, to avoid outages. This overloading is a current issue, not one for future planning. We were lucky this year. What might have happened had we had longer stretches of extreme heat as we did in 2011?

Until put on hold by the City Council, installation of the Mill Creek substation was part of Water & Light’s contingency plan to keep the system up and running under adverse conditions. (Compare these 2016 maps which show the system without Mill Creek, and with its addition.)  “Load shedding” is a focus of the current plan. This was explained to the City Council in January 2018, although it did not draw much discussion. Where would outages occur? Depending on where the load needed to be dropped, outages would start with the circuits tied to that particular substation and after that, would occur on circuits identified “from a priority or community impact relationship.” (Minutes, January 2, 2018, pp. 13 and 14.)

How would your business, residence, or our community be affected by an extended outage? Is this a risk we are willing to simply live with? If not, speak up! Electric infrastructure takes time to plan and install. We have 11 months before next summer. This is an urgent issue that needs ongoing attention.  Can we develop an action plan for Vision: Lights On!?

02.20.18
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More on Transmission

We have written before about the City Council’s January 2016 decision to pause construction on a much needed substation and transmission line with no alternative plan in place. Two years have passed and we still do not have a plan, nor have we received the benefit of paying the higher rates that were put in place to fund the construction.

In recent months, some council members have suggested this substation and line project was never really needed.  That is incorrect as is explained in this op-ed which was recently published in the Columbia Tribune.  We are running out of the capacity to reliably deliver electricity downtown, and straining the grid throughout the South and Southwest.

And we still do not have a plan.  We do have a new planning process (still to be defined) and we continue to spend on researching alternatives.  We paid $10,000 to Ameren for an additional study of the proposed “Option E” concept and in September of 2017 the council approved an additional $95,515 to further study that Option, which Ameren has estimated would cost $25 million for 10 miles of line (an estimate that does not appear to include the city’s costs of acquiring easements).  That Option also would not solve the substation overloading issue.  The City and Ameren are also exploring building a new switchyard and substation in west Columbia and then running a new 161 kV line into the Perche Creek substation.

The proposed “purpose and scope” describing the new planning process that was attached to the January 2, 2018 memo to the city council noted that the studies for Option E would be incorporated into the new planning process but did not mention also incorporating the engineering and surveying for the original project which cost more than $2 million.  Why?  A January 2018 5th Ward newsletter suggested that the original plan had been abandoned, and a 12/22/17 staff memo suggested it had been “canceled”. When?  By whom?  (There have not been subsequent council hearings or votes). Why wouldn’t all options remain on the table as we consider what would best meet our needs?

What is occurring on this issue falls short of the straightforward, open dialogue that citizens want and need on our infrastructure issues. As was recommended in past forums, we would benefit from a more citizen-centered planning process that is proactive, transparent, and focused on ensuring the key needs are timely met in a cost-effective way

 

10.20.16
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Information and Misinformation – 1

As a community we want to make wise decisions about our infrastructure and our future.  Wise decisions require consideration of facts, needs, and consequences. On January 19 of this year, the City Council voted to  “pause”  the building of an electric transmission line and substation that had been approved by voters in 2015 and for which bonds had been issued. The Council has not announced when it will again review this “pause” nor has it talked much about how the pause is affecting economic development or our electric service.  City staff, however, recently announced that it is preparing a request to extend the moratorium on building downtown due to concerns with electric infrastructure.

We asked Connie Kaprowicz of Columbia Water & Light, who joined us in the August on-line Trib Talks forum, to help us understand some of the issues involved.

1C1C: When we look at past forums, new articles, and on-line comments, we seem to be talking about two things, the Mill Creek substation and the overall  transmission line. Can you explain why each is needed and how these inter-relate?

W& L: Electricity is generated at a power station or power plant from fossil fuels or renewable resources. Approximately 90% of Columbia’s energy comes from sources outside the city. Once the power is generated, it has to be moved to where it is going to be used. Large amounts of power are transferred with electric transmission lines. An interconnected network of transmission lines is commonly referred to as the power grid.

Transmission lines feed into substations. At substations, transformers step down the power to lower voltages. From there, power is delivered to individual electric customers by distribution lines.In the older sections of town, distribution lines are mounted on wooden poles. New distribution lines in Columbia must be placed underground according to city ordinances.

electric system diagram

1C1C: Does the Mill Creek Substation still need to be built even if the transmission line is built on a route other than Option A?

W & L: Yes, As noted above, the Mill Creek substation is needed due to the electric load growth in the southern area of town. Our other substations serving the area are loaded over the suggested amount. As we explained at our May work session presentation, electric systems must have reserved capacity for times of high loads and/or problems with the system such as those caused by storms. Both the Hinkson and Perche substations are overcapacity as shown in the chart below.

  • Substation loading goal: two transformers at 50%, three transformers at 66.6%
Year Grindstone (3*) Hinkson (3*) Perche (2*)
2007 41.5% 67.6% 61.8%
2010 44.7% 68.6% 64.4%
2015 48.6% 64.2% 72.0%

*number of transformers

1C1C: Suggestions were made in past forums and in Trib Talk that rather than building the Mill Creek substation, additions could just be made at another substation like Hinkson. You indicated in our August on-line forum that that was not a good option. Could you explain in layman terms why?

W & L: There is not room to expand the Hinkson Creek substation. Even if the University would sell us additional land, it is not the best site since it is prone to flooding. Even then we would still need to build transmission lines to get the power to where it is being used. That would involve running lines through the south side of town.

We have also already purchased the land for the Mill Creek substation which is in a better spot geographically to serve the southern side of town.

1C1C: You indicated in the August on-line forum that even if we went with the suggested alternate route for the transmission line, which has been dubbed “Option E”, additional transmission lines would still be needed on the south side of town. Can you say more about that?

W & L: Option A resolved two technical issues: One is providing a second feed into the Perche Creek substation and the other is to reduce substation loading (see info above). Option E, which was proposed by the Mayor at a council work session in May, 2016, addresses the issue of getting a second 161 kV feed to Perche substation. It does not address the need to reduce substation loading. There was no direction from the City Council on how they would like to tie the Mill Creek substation into the transmission and distribution system in the event that the transmission line route changed. So that issue would still need to be resolved.

1C1C: One of the ideas about Option E was that we might be able to place our lines on poles owned by Ameren UE and Associated Electric. What is the status there?

W & L: After the Mayor proposed Option E we first needed to do some modeling work. Modeling work evaluates any possible engineering problems that could impact the entire system so it is very time consuming. Think of it as looking at all the things that can happen during one minute of play during a team sport. There are many different possibilities and combinations of things that could present risk. After our modeling did not find any red flags, we sent our modeling work to our neighboring utilities to analyze and get back to us. We do not have a response yet from any of them. Once we do hear back from them, we could possibly do another work session with council to see if they want us to pursue Option E. We still need feedback on what to do about the Mill Creek substation.

1C1C: During our August forum at least one citizen suggested that we need not be concerned about delay in moving forward with these projects because the electric system didn’t shut down over the summer. Can you comment on that?

W & L: In our personal lives, living without electricity is hard. For businesses, it can impact their income and level of service to their customers. During the storm in 2014, the wooden 80’ tall transmission poles on Fairview snapped and it took some of the largest line trucks in the Midwest to repair them. The outage from this storm lasted for five days for some of the customers. Every situation is different when it comes to problems. Small transformers on distribution lines can be easily replaced. Damage or equipment failure at the substations could take weeks/months. That is why we plan for redundancy and reserves.

Think of a road system. When there is construction or an accident you have to detour. The electric transmission and distribution system should never be run at 100% because space is needed if we need to isolate a problem and serve customers from another line. Unlike traffic, electricity can’t get stuck in a traffic jam because overloading (heavy traffic) could cause cascading problems. This would be like what happened on the east coast in the early 2000s.

Reserves refers to having extra energy available to serve an unexpected peak. This is federally regulated as well. We have to show what our peak usage is and then secure extra energy resources beyond that. All of this a part of keeping the electric grid reliable.This summer we were close to a new electric peak but luckily it rained and a cold front moved in.

Transmission planning is complex and takes time. We first identified the need for this project in 2004 when our models indicated we would have issues with the system even under normal conditions by 2020, taking into account growth. At present, we could experience problems even before 2020, particularly if any element of the system is out of service (weather, malfunctioning equipment, etc). I personally do a lot of worrying during every storm and during periods of hot, humid weather when it doesn’t cool down much at night.

1C1C: In an earlier chat you mentioned that the  Average Electric Service Availability Index is 99.9876 for Columbia out of a hundred and that a drop in this could hurt our economic development efforts. Please expand on this. 

W & L: Our community has invested in our electric system since 1904 so it is reliable. Having a reputation of unreliable electric service is not a good thing when we seek new businesses in our community. Reliability is affected by a number of factors related production, demand from customers, and delivery. Many people don’t realize that unlike water or natural gas, electricity can’t be stored by utilities in large amounts (existing batteries for use with solar energy production are very expensive and can only store a small amount) . Electricity also does not run in one direction through a “pipe” like water or natural gas. Electrons move in different ways which is one of the things that makes electrical engineering a specialized and complex field. Businesses – particularly those that are energy intensive or, like medical facilities, that rely on equipment that is sensitive to fluctuations in power, – are concerned about both power quality (avoiding fluctuations in voltage) and availability on demand.

1C1C: Can you say more about “availability on demand”?

W & L: Because electricity can’t be stored, an electric utility has to provide the power needed at every minute of the day, even as the level of demand varies. Although the amount of electricity that the city needs over time is measured in kilowatt hours the level needed at any given time is referred to as “demand”. If everyone in Columbia, especially commercial customers with large equipment, turned on everything all at once for 2 minutes, we would have to meet that huge demand for those 2 minutes. Meeting that demand is not just a matter of producing the electricity – we have to deliver it as well. This means that our transmission and distribution systems must be robust enough to meet any spikes in demand at any given moment in time. Our ability to deliver is affected by both transmission and distribution constraints. In an ideal world, demand would be constant throughout every minute of the day. We don’t live in an ideal world, and that is why we have to build a system that can handle spikes in demand. Since large commercial customers and industrial customers demand can have a big impact on our system, they are charged a kilowatt hour charge (like residential) but they also have a separate demand charge. The following graphic will help you understand energy v.demand for our system.

1C1C:  Thank you Connie.  To our readers, continue to check this blog for more posts in this series!