While hundreds of megawatts of new solar power projects have been approved by US states and municipalities recently, the question of where associated transmission lines will be sited still hangs over some of these developments.
The availability of transmission lines that could carry planned utility-scale solar energy generation to urban centers in the US is still lacking in many areas, particularly the Southwest, where solar insolation is the highest.
Ten year transmission line plan for the West
In response to the overwhelming need for an upgraded and extended transmission line system particularly in the west of the country, WestConnect, a company that connects western US utility companies, plans to carry out 183 transmission projects in nine western states over the next decade. This plan represents a capital investment of at least US$13.3 billion, according to the 2015 WestConnect annual 10-year transmission plan released earlier this month.
The planned transmission line projects have a total length of 5,334 miles and include work on 75 transmission lines, 39 substations and 28 transformers, according to the plan.
In addition to this, there are 75 conceptual transmission projects in the plan with a total combined length of 6,920 miles and representing a capital investment of at least US$12.1 billion.
Capital investment data was not provided for 18% of the planned projects and for 25.3% of the conceptual projects.
WestConnect’s 2015 plan is the eighth regional transmission plan coordinated and produced on behalf of WestConnect subregional planning participants and stakeholders, and encompasses three sub-regional planning areas that cover all or parts of South Dakota, Nebraska, Montana, Wyoming, Colorado, New Mexico, Arizona, Nevada, and California.
The plan is scheduled for approval at the next WestConnect Annual Planning Meeting in mid February.
Here is a list of some of the projects:
· In Arizona, there are 66 planned projects with 55 line miles and an investment of US$722 million
· In California, there are 21 planned projects with 815 line miles and an investment of US$3.2 billion
· In Colorado, there are 26 planned projects with 386 line miles and an investment of US$532 million
· In Nevada, there are 21 planned projects with 23 line miles and an investment of US$248 million
· In New Mexico, there are 15 planned projects with 107 line miles and an investment of US$131 million
· In Texas, there are 12 planned projects with 14 line miles and an investment of US$34 million
· In Wyoming, there are six planned projects with 217 line miles and an investment of US$108 million
The 2014 WestConnect 10-year plan for the region had 199 planned transmission projects with an estimated total capital investment of more than US$14.5 billion. In addition, in last year’s plan, there were 66 total conceptual projects with an estimated total capital investment of over US$12.1 billion.
California needs transmission lines to meet renewable goals
California has been a US leader in driving up the renewable – and particularly the solar – component of utility generating portfolios. The state has been working diligently toward its nation-leading Renewables Portfolio Standard, which will require an estimated 15 to 20GW of renewable energy by 2020. [Engerati – California Invests in its Clean Energy Future.]
California represents approximately 80% of the market for renewable energy generated in the western states.
California expects to spend some US$15.7 billion in building new transmission lines to meet its current renewable energy goal of 33% of total capacity by 2020, led by the California Independent System Operator (CAISO).