Terra-Gen LCC

Increases overall revenue with DEIF control retrofit solution

Prolonged lifetime and an increased overall revenue by retrofitting aging wind turbines

The independent power producer Terra-Gen, LLC frequently experienced downtime with their Vestas* V47 wind turbines on its high-wind site in Pacific Crest, Mojave. It goes without saying that something needed to be done and a control retrofit seemed like the obvious solution.


DEIF engineer upgrading Terra-Gen LLC windmills with a control retrofit solution.

The California-based company looked for an experienced partner and got in contact with DEIF who has a long track record in retrofitting the Vestas* V47s.

Based on thorough analysis and matching of expectations, the team from DEIF presented a business case that not only would optimize the turbines’ performance but also make Terra-Gen, LLC independent in terms of VRCC related costs such as spare parts, lost production due to downtime and derating.

Harvesting increased availability without the VRCC

DEIF’s control solution includes new technology that enables a more efficient turbine operation without the VRCC unit. Terra-Gen, LLC will benefit on an increased availability factor, advanced derating features, yaw algorithms and adaptive power set point to keep the turbines maximum energy output.  Basically, Terra-Gen, LLC increases revenue and lowers the operating costs.

Short payback time and prolonged lifetime

Only in three years, Terra-Gen, LLC should see a positive return on investment and the wind farm owner is positive.


"We believe that our customers should have free access to all collected data - after all it is their wind turbines. Data access enables owners and service crew to analyze the health of the equipment and troubleshoot faster."

Jean S. Felber |

Full data access

Besides having extended the lifetime of their wind turbines, tttv also have free access to all available data enabling them to continuously optimize their business.

Performance optimization & lifetime extension

The increased demand for competitive power production and the rapid development in the wind industry necessitates that older turbine models such as the Vestas* V47 are equipped to meet today’s performance standards. DEIF’s control retrofit solution extends the turbine lifetime and optimizes the turbine performance in terms of variable speed concepts, extended cut-out and adaptive power set point.

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*) “Vestas” is a trademark of Vestas Wind Systems A/S. The trademark owner is not associated with our products or services

“We strive to run our turbines efficiently – at the lowest cost. The Pacific Crest Wind Farm is a high wind site and the cost of downtime is critical. So, with the controller upgrade and thus performance optimization, I am convinced that we will extend turbine lifetime, reduce our downtime and increase the revenue of the total wind farm”

Ward Scobee |

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