1. Why are power plants, lines and substations necessary?
2. How does electricity arrive at my home?
3. Why doesn't Idaho Power place power lines underground?
4. Isn't it better to place lines underground?
5. Is it more expensive to put transmission lines underground?
6. Why does it cost so much more?
7. Does that mean transmission lines cannot be placed under ground?
8. Why can't Idaho Power pay the difference in cost?
9. How will Idaho Power address our concerns related to transmission line aesthetics?
1. Why are power plants, lines and substations necessary?
Idaho Power Company provides an essential service. We take our obligation to serve residents, businesses and governmental entities throughout the state very seriously. As a regulated utility our company is required to construct and maintain the necessary electric facilities needed to distribute electricity from generating plants to our customers.
2. How does electricity arrive at my home?
Electrical lines and facilities are a necessary part of the infrastructure
within any community, just like roads, water and sewer facilities. Much like
our highway system, Idaho Power's 24,000-square-mile power-line grid is made
up of large and small lines. Larger transmission lines operate somewhat like
interstate highways and freeways. Electricity flows on this electric "freeway"
to a substation, where it is reduced to a lower voltage and sent out again
on distribution lines. These smaller distribution lines operate like streets
and avenues that crisscross communities and neighborhoods. Many are needed
to get from one destination to another.
3. Why doesn't Idaho Power place power lines underground?
It is not that uncommon today for the smaller distribution lines in a new subdivision,
for example, to be installed underground. The cost of placing the lines underground
becomes the responsibility of the developer or the homeowner. In the case of
the smaller distribution lines, the extra cost may be manageable for those
who request it. Idaho Power's responsibility is to provide cost-effective power
to customers, and the most affordable industry standard is overhead power lines.
4. Isn't it better to place lines underground?
Idaho Power does not oppose placing lines underground. However, it is important to note there are pros and cons to building lines overhead and underground. The reliability of overhead and underground lines is comparable. For instance, both underground and overhead lines are subject to damage from lightning. Although overhead lines may have more exposure than underground lines to wind damage or collisions, underground facilities are more prone to flood damage and dig-ins.
Key differences between underground and overhead lines are that it typically takes more time with underground lines to diagnose a problem and perform the repair. Once underground lines are built, it is impractical to modify them as conditions change around them. The difference in repair time is best characterized in days rather than hours.
5. Is it more expensive to put transmission lines underground?
Yes. Transmission lines supply power to larger areas and more customers than distribution lines, and they are much more expensive to build. The extra cost of placing these lines underground is quite significant. An equivalent underground transmission line can cost five to 15 times more than the cost of an overhead transmission line.
6. Why does it cost so much more?
Transmission lines can provide enough electricity to power whole cities and are much more technically complex and material intensive in order to transport larger amounts of power. Each underground transmission line is custom-made, and as such they are very expensive to design, install and maintain.
7. Does that mean transmission lines cannot be placed under ground?
If engineering complexities and cost differentials can be overcome, Idaho Power is open to the idea of underground transmission.
If a community decides that it wishes a line to be placed underground, the residents who benefit from this action must be willing to pay the extra costs involved. And, of course, as with any business transaction, the community requesting underground lines must be able to show that they have the means to pay for the construction.
8. Why can't Idaho Power pay the difference in cost?
As a regulated utility, Idaho Power is required to provide safe, reliable, low
cost electric service to its customers. The public utility commissions of Idaho
and Oregon authorize the rates Idaho Power can charge its customers in their respective
jurisdictions and determine what costs can and cannot be included in those rates.
It is the regulators' policy, and Idaho Power agrees, that it is unfair to ask
all of Idaho Power's customers to pay for a benefit received by only a limited
number of customers.
Consequently, Idaho Power will consider the option to bury lines only when another entity agrees to pre-pay feasibility study costs and pick up the differential cost between underground and overhead construction. Idaho Power has approximately 4,671 pole miles of transmission lines on its system and 25,237 miles of distribution lines. Idaho Power does not currently have any transmission lines underground, while approximately 5,866 miles of the distribution lines are underground.
9. How will Idaho Power address our concerns related to transmission line aesthetics?
As homeowners and residents ourselves, who live in communities served by Idaho Power, we share the desire for an aesthetically pleasing community. Typically, Idaho Power's engineers will find routes that follow busy roadways. They also look for opportunities to rebuild existing lines or build next to existing lines. When constructing new power lines, they may incorporate smaller distribution lines on the same poles to reduce the clutter of multiple lines in an area.
Once the route is sited, careful placement of individual poles — such as around neighborhood entrances and adjacent to property lines — may be used to minimize the transmission line's effect on the appearance of an area. Idaho Power crews will clean up and restore the area where improvements have been made. Further, we ask communities to help us by sharing their concerns, asking questions, and providing input on the siting, installation and mitigation (landscape and design) of Idaho Power facilities. This helps us propose projects with the least impact on the community as possible.