HVDC Transmission is Hot
Renewables Fueled Resurgence
๐๐ฉ๐๐ ๐๐ฟ๐ฎ๐ป๐๐บ๐ถ๐๐๐ถ๐ผ๐ป ๐ถ๐ ๐ต๐ผ๐.
As hot as transmission gets at least.
๐๐ฉ๐๐ ๐ถ๐ ๐ป๐ผ๐ ๐ป๐ฒ๐ ๐๐ฒ๐ฐ๐ต๐ป๐ผ๐น๐ผ๐ด๐, but the changing generation mix (read: ๐ฟ๐ฎ๐ฝ๐ถ๐ฑ ๐ฑ๐ฒ๐๐ฒ๐น๐ผ๐ฝ๐บ๐ฒ๐ป๐ ๐ผ๐ณ ๐ฟ๐ฒ๐ป๐ฒ๐๐ฎ๐ฏ๐น๐ฒ๐) has put additional premia on the strengths of HVDC transmission. For example, HVDC:
๐๐๐ณ๐ณ๐ถ๐ฐ๐ถ๐ฒ๐ป๐๐น๐ ๐๐ผ๐ป๐ป๐ฒ๐ฐ๐๐ ๐ฅ๐ฒ๐บ๐ผ๐๐ฒ ๐ฅ๐ฒ๐ป๐ฒ๐๐ฎ๐ฏ๐น๐ฒ๐: Minimizes long-distance power loss, vital now for affordably integrating vast wind (like Prairie wind) and solar resources to meet climate targets (see NRELโs map of resources, population centers, and the โWI-EI Seamโ).
๐๐๐ผ๐ผ๐๐๐ ๐๐ฟ๐ถ๐ฑ ๐๐ผ๐ป๐๐ฟ๐ผ๐น & ๐ฅ๐ฒ๐น๐ถ๐ฎ๐ฏ๐ถ๐น๐ถ๐๐: Seamlessly links unsynchronized grids (e.g., between provinces) and offers precise power flow control, essential today for managing variable renewables and enhancing stability.
๐๐๐ป๐ฎ๐ฏ๐น๐ฒ๐ ๐๐ถ๐ณ๐ณ๐ถ๐ฐ๐๐น๐ ๐ง๐ฟ๐ฎ๐ป๐๐บ๐ถ๐๐๐ถ๐ผ๐ป ๐ฅ๐ผ๐๐๐ฒ๐: Superior for long underwater/underground cables, crucial now for offshore wind and building lines through dense or sensitive areas where overhead AC struggles.
๐๐ฃ๐ฟ๐ผ๐๐ถ๐ฑ๐ฒ๐ ๐๐ฑ๐๐ฎ๐ป๐ฐ๐ฒ๐ฑ ๐ฉ๐ฆ๐ ๐ง๐ฒ๐ฐ๐ต๐ป๐ผ๐น๐ผ๐ด๐: Modern VSC-HVDC offers better control, grid support, and flexibility, meeting the complex needs of today's renewable-dominant power systems.
The strong match between the strengths of HVDC and the needs of the grid means that some of the most notable transmission projects in the US are HVDC projects. A few examples:
๐ฃ๐ฟ๐ผ๐ท๐ฒ๐ฐ๐๐ ๐จ๐ป๐ฑ๐ฒ๐ฟ ๐๐ผ๐ป๐๐๐ฟ๐๐ฐ๐๐ถ๐ผ๐ป ๐ผ๐ฟ ๐ก๐ฒ๐ฎ๐ฟ๐ถ๐ป๐ด ๐๐ผ๐บ๐ฝ๐น๐ฒ๐๐ถ๐ผ๐ป: ๐๐ฉ๐ฆ ๐๐ถ๐ฏ๐ก๐ช๐ข ๐๐ณ๐ข๐ฏ๐ด๐ฎ๐ช๐ด๐ด๐ช๐ฐ๐ฏ ๐๐ณ๐ฐ๐ซ๐ฆ๐ค๐ต (Pattern Energy) is a 550-mile, ยฑ525 kV DC line under construction, delivering 3,000 MW of wind power from New Mexico to Arizona. ๐๐ฉ๐ฆ ๐๐ฉ๐ข๐ฎ๐ฑ๐ญ๐ข๐ช๐ฏ ๐๐ถ๐ฅ๐ด๐ฐ๐ฏ ๐๐ฐ๐ธ๐ฆ๐ณ ๐๐น๐ฑ๐ณ๐ฆ๐ด๐ด (๐๐๐๐) (Transmission Developers Inc. with Hydro-Quรฉbec) is a 339-mile, ยฑ300/320 kV DC underground/underwater line, also under construction, transmitting 1,250 MW of hydropower from Quรฉbec to New York City.
๐ฃ๐ฟ๐ผ๐ท๐ฒ๐ฐ๐๐ ๐ถ๐ป ๐๐ฑ๐๐ฎ๐ป๐ฐ๐ฒ๐ฑ ๐๐ฒ๐๐ฒ๐น๐ผ๐ฝ๐บ๐ฒ๐ป๐ ๐๐ถ๐๐ต ๐๐ถ๐ด๐ต ๐๐ฎ๐ฝ๐ฎ๐ฐ๐ถ๐๐: ๐๐ฉ๐ฆ ๐๐ณ๐ข๐ช๐ฏ ๐๐ฆ๐ญ๐ต ๐๐น๐ฑ๐ณ๐ฆ๐ด๐ด (Invenergy Transmission) is an 800-mile, ยฑ600 kV DC overhead line in advanced development, aiming to deliver up to 5,000 MW of wind energy from Kansas to Indiana (starting at 2,500 MW). ๐๐ฉ๐ฆ ๐๐ณ๐ข๐ฏ๐ด๐๐ฆ๐ด๐ต ๐๐น๐ฑ๐ณ๐ฆ๐ด๐ด (๐๐๐) (TransWest Express LLC) is a 732-mile, ยฑ600 kV DC line in pre-construction, set to transmit 3,000 MW of wind energy from Wyoming to the Desert Southwest. ๐๐ฉ๐ฆ ๐๐๐ ๐๐ณ๐ฆ๐ฆ๐ฏ ๐๐๐๐ ๐๐ช๐ฏ๐ฌ (Direct Connect Development Company) is a 350-mile, ยฑ525 kV DC underground line along railways, in advanced development, carrying 2,100 MW from Iowa to Illinois.
๐ฃ๐ฟ๐ผ๐ท๐ฒ๐ฐ๐๐ ๐ถ๐ป ๐๐ฎ๐ฟ๐น๐ถ๐ฒ๐ฟ ๐๐ฒ๐๐ฒ๐น๐ผ๐ฝ๐บ๐ฒ๐ป๐ ๐๐ถ๐๐ต ๐ฅ๐ฒ๐ด๐ถ๐ผ๐ป๐ฎ๐น ๐๐ผ๐ฐ๐๐: ๐๐ฉ๐ฆ ๐๐ณ๐ฐ๐ด๐ด-๐๐ช๐ฆ ๐๐ณ๐ข๐ฏ๐ด๐ฎ๐ช๐ด๐ด๐ช๐ฐ๐ฏ ๐๐ณ๐ฐ๐ซ๐ฆ๐ค๐ต (Xcel Energy) is a 214-mile, ยฑ500 kV DC line in development, designed to deliver 1,500 MW between Colorado and New Mexico, enhancing SPP-WECC connectivity. ๐๐ฉ๐ฆ ๐๐ช๐ฎ๐ข๐ณ๐ณ๐ฐ๐ฏ ๐๐ช๐ฏ๐ฌ ๐๐ณ๐ข๐ฏ๐ด๐ฎ๐ช๐ด๐ด๐ช๐ฐ๐ฏ ๐๐ณ๐ฐ๐ซ๐ฆ๐ค๐ต (NextEra Energy Transmission) is a long-distance, ยฑ525 kV DC line in development/permitting, potentially moving 4,000 MW of wind energy from Oklahoma to Missouri and eastern interconnections.
๐๐ฉ๐๐ ๐ถ๐ ๐ป๐ผ๐ ๐ป๐ฒ๐ ๐๐ฒ๐ฐ๐ต๐ป๐ผ๐น๐ผ๐ด๐, but itโs resurgence is being driven by new technologies like solar and wind.
๐ช๐ต๐ฎ๐ ๐ผ๐๐ต๐ฒ๐ฟ ๐ข๐๐ ๐ฒ๐ป๐ฒ๐ฟ๐ด๐ ๐๐ฒ๐ฐ๐ต๐ป๐ผ๐น๐ผ๐ด๐ถ๐ฒ๐ ๐ฎ๐ฟ๐ฒ ๐๐ฒ๐ฒ๐ถ๐ป๐ด ๐ฎ ๐ฟ๐ฒ๐๐๐ฟ๐ด๐ฒ๐ป๐ฐ๐ฒ (๐ป๐๐ฐ๐น๐ฒ๐ฎ๐ฟ ๐ฐ๐ผ๐บ๐ฒ๐ ๐๐ผ ๐บ๐ถ๐ป๐ฑ)?