Vaisala Supports SunEdison, TerraForm in $2.4B First Wind Acquisition

Vaisala 3TIER Services selected to deliver crucial asset valuation analysis to help finalize purchase decision

Vaisala, a global leader in environmental and industrial measurement, played a critical role in supporting SunEdison Inc., and its power-plant holding company, TerraForm Power Inc., in the $2.4 billion purchase of First Wind Holdings Inc. in late 2014.

Prior to the acquisition of a large number of assets in any industry, it is imperative that the value of those assets is accurately assessed and quantified. When the assets involved are wind projects both fueled and impacted by the weather, bringing in experts to translate weather information into energy production estimates and project valuation decisions is vital.

With the purchase of First Wind, TerraForm gained 521 MW of active wind and solar power plants and more than 8 GW of total pipeline, backlog, and leads. Prior to finalizing the deal, asset valuation was required to determine the worth of First Wind's existing portfolio. Vaisala was selected by SunEdison to deliver the necessary analysis to evaluate key development assets.

Making sure the worth of this portfolio was calculated accurately was highly dependent on robust climate and energy analysis. However, when it came to closing the deal, all parties involved were also working against tight deadlines and needed to act as quickly as possible to complete the financial due diligence for such a major investment. To fulfill these two requirements, SunEdison turned to Vaisala.

"When negotiating such an important and sizeable acquisition, time pressure can be considerable and the ability to act fast can make or break a deal," said Barnaby Olson, Director of Special Projects at SunEdison. "It's nonetheless critical for the success of the investment that early due diligence work is both thorough and comprehensive."

"Having worked with Vaisala 3TIER Services in the past, we were well aware of the team's competency, dedication, and ability to turn work around extremely quickly - and these attributes were invaluable to us as we successfully finalized the purchase of First Wind."

Vaisala completed analysis on 377.5 MW, or nearly a quarter of First Wind's development portfolio, on an accelerated timeline to accommodate the transaction. This work entailed quality control analysis of available meteorological tower data at the project sites to deliver long-term net production numbers, calibrated to local conditions, with all loss values incorporated (such as, wake deficits, extreme weather, and electrical and grid downtime).

The First Wind acquisition has been characterized as a transformative move to diversify the range of renewable energy projects SunEdison can develop and to aggressively increase its portfolio.

Vaisala has carried out asset valuation analysis on both operational and in development wind projects totaling over 30 GW of wind capacity worldwide. For more information about the range of services offered by Vaisala to the renewable energy sector, please visit

Vaisala Energy
Weather is the largest variable impacting electricity generation, transmission, and demand and it provides the fuel for renewable energy projects. Energy customers work with Vaisala to support efficient, reliable, and profitable electrical energy systems around the globe with a wide range of measurement, assessment, forecasting, and asset management products and services. Our real-time and historical lightning information ensures continuous energy generation, improved safety, and reduced costs in both energy production and transmission. Renewable energy developers and operators use Vaisala equipment and services to support the entire project lifecyle, from greenfield prospecting and due diligence to operational forecasting and plant optimization.

About Vaisala
Vaisala is a global leader in environmental and industrial measurement. Building on 79 years of experience, Vaisala contributes to a better quality of life by providing a comprehensive range of innovative observation and measurement products and services for chosen weather-related and industrial markets. Headquartered in Finland, Vaisala employs approximately 1600 professionals worldwide and is listed on the NASDAQ OMX Helsinki stock exchange.

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