When you hear the word voltage, one might think of a lightning bolt, which has millions of volts. By comparison, your typical residential outlets provide 120 volts. Which makes sense why lightning bolts, while short, cause much destruction.
This article highlights voltage levels provided by utility companies and how this impacts consumers and businesses daily.
Voltage levels can be categorized into three general classes:
Transmission voltage, and two types of Distribution Voltage – Primary Distribution Voltage and Secondary Distribution Voltage.
So, what is the difference between these two voltage levels, and why are they important as a large consumer?
It is important to remember voltage levels vary for multiple reasons, however the primary reason is equipment. Electric end-use equipment, whether lights, air conditioning or motors, have certain voltage level requirements needed to operate. For example, your air conditioning system at home requires 240v whereas your outlet plugs require 120v.
A commercial customer, however, may need voltage levels at 480v or higher to operate larger equipment. As such, all-residential voltage is provided to the meter providing 120v and 240v.
For commercial and industrial customers, there are options to voltages and at what level voltage is served. Commercial customers may sometimes have the option of metering voltage at the primary voltage level and larger industrial type customers may meter voltage at the transmission service level.
For Primary voltage service level, this means that the utility meter is metering at a little above 9,000 volts and prior to the electricity being stepped down by a transformer to a usable voltage, i.e., 480, 240, or 120v.
When the electricity market deregulated in Texas, the rules for utilities serving at different voltage levels changed. The new rule was not favorable to consumers, disallowing a regulated utility to offer rental facility, i.e. transformer and conductor. The rule of thumb with the new rule was, if it is competitively available in the opern market then a regulated utility could not offer the service anymore. If a customer wanted to be metered at the primary service level, the customer was and is now required to own their own transformer. This usually comes at a high upfront cost but can pay for itself over time. Nevertheless, there was a public outcry from consumers who were primary metered and did not want to purchase or own their transformer facilities. As such, several customers throughout ERCOT (Electric Reliability Council of Texas) were grandfathered into their primary voltage configuration where they continue to pay a utility a rental facility fee for the use of the utilities transformer while still being metered at the primary voltage level, while some other customers purchased transformers from utilities to maintain their primary voltage status. Those customers that purchased their facilities were not required to continue rental facility fee payments, however, they were now responsible for the performance of the equipment and were responsible for replacing equipment if need be. Most customers preferred the legacy program where a rental facility fee was / is in place and the utility takes responsibility for equipment performance. So, what is the or was the benefit to do it this way?(DV, hope this answers the question)
For Transmission voltage service level, this means the utility meter is metering at 69,000 volts, 138,000 volts or sometimes 345,00 volts depending on the transmission line. In all cases metering occurs prior to electricity entering a customer owned substation where voltage levels step down from transmission voltage levels to distribution voltage levels.
These metering voltage options available to a consumer are decided by multiple factors, the main reason being the size of the load, equipment location, and Capex dollars that may not be available.
In most cases voltage will be served at the secondary distribution level. Which means your electric meter is positioned somewhere behind a utility transformer or transformer bank which may be on a pole or pad mount near your facility. In this scenario line losses are the highest. Line losses occur when voltage goes through a transformation, such as stepping down from 9,000 volts to a lesser voltage range. – Not sure people will understand this point can you explain it is the first time you use the term line losses. However, the utility owns and is responsible for all equipment prior to the meter, so the utility is responsible for the Transformer and its performance.
Line losses are an important variable in these configurations given they are not as highthe amount of electiricty that is lost is mitigated (what does as high mean – can we say it differently? when metered at higher voltage levels and electricity does not have to be reduced to a lesser voltage range. Utility regulated tariffs are also lower when metering occurs at higher voltage levels, as well as retail power costs, so it is a one, two, three savings benefit.
As electricity is transformed from 345,000 KVA or 138,000 KVA to 9,700 KVA to 480,240, 120 KVA voltages, significant loss of electricity occurs during that voltage transformation process. In fact, losses begin as soon as electricity leaves the power plants’ main busbar on its journey to energize a piece of your equipment. The preference is to avoid line losses as much as possible which means metering at the highest voltage level possible. This however is difficult to achieve if your overall power consumption does not merit the added cost of metering at higher voltages requires. Nevertheless, line loss factors are calculated guesses that retail suppliers must take into consideration when estimated costs. These costs can vary significantly from one retail supplier to another. Line losses are considered one the big ticket items in a fixed retail price. So how does it impact my costs if at all?
Retail entities recover the cost of line losses which vary from one consumer to another depending on how power is consumed. Utility tariffs also vary based upon the type of voltage levels being served or delivered.provided per their regulated tariffs.
Unfortunately, the Transmission /, Primary voltage scenarios are sometimes not clear cut as to what type of customer load is best suited for these higher service levels. facility would make sense. However, in most cases, transmission service usually entails an exceptionally large consumer load upwards of 20 Megawatts. Whereas Primary distribution may occur at levels between 5 to 20 MW. Large industrial entities such as refineries, steel mills, chemical plants have their own substations and are typically served at the transmission level.
There are situations where a load that is large enough merits discussion of transmission or primary voltage, which means a consumer will have to purchase, own and be responsible for its own subtation and or transformers, respectively.
r.The purpose of sharing and or reminding consumers of different voltage levels is to highlight the pros and cons of taking voltages at different levels as well as help explain the important cost variable of line losses which is a physical phenonmena that occurs when voltage is transformed. Consumers are also reminded that line losses are a “big ticket” item when it comes to retail power prices and are an added cost component that is not the same across retail providers.
Can you do a wrap up for the read- telling why you shared this information?
Whether you are a greenfield location or an existing facility that is considering reconfiguring your electrical services, We here at Acclaim are here to help you understand your options and will guide you to the most beneficial voltage levels that make sense for your facility. In most cases, secondary distribution voltage will apply, however, under certain circumstances it is worth considering alternative voltage levels that will yield significant savings over the long run.