PHOTON NEWSLETTER - According to the third edition of North America Renewable Energy Brief from US national professional services firm CohnReznick LLP, yieldcos have raised $19 billion through IPOs, secondary offerings, and various debt instruments over the past two and a half years.

Of this sum, $11.3 billion was secured by yieldcos in debt and equity in the first three quarters of 2015.

Terraform Power and Terraform Global, the two yieldco vehicles launched by US renewable energy company and solar manufacturer SunEdison Inc., were able to reach a market share of 32% and 17%, respectively, in the first three quarters of this year.

Furthermore, CohnReznick reports that yieldcos were able to acquire 6.5 GW of effective capacity in the first nine months of 2015, up from 6.0 GW of capacity acquired during all of 2014 and 3.5 GW in 2013.

In the period from January to September 2015, Terraform Power was the largest acquirer of renewable energy assets with 2.3 GW of capacity, followed by Terraform Global (1.3 GW), NRG Yield Inc. (812 MW) and NextEra Energy Partners (664 MW).

The report stresses that yieldocs are now being challenged on a number of fronts. A part from tumbling stock prices, yieldcos will now have to deal with the pending expiration of the 30% solar ITC at the end of 2016.

"Some yieldcos don’t have as much transparency as investors would like to see," said C ohnReznick's Ron Sternthal. "So investors have started to question this and it is a big issue. The assets don’t grow in value like real estate because they depreciate. So, they constantly need to acquire new assets to grow. The bigger they get, the more assets yieldcos need to acquire to grow at the same pace."

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