(Adds details from complaint, comment by Vivint, other background)
March 8 (Reuters) - New Mexico's attorney general on Thursday sued Vivint Solar Inc, alleging the company engages in unfair trade practices when signing up customers for its residential solar contracts.
Vivint, one of the nation's largest rooftop solar installers, said the lawsuit was without merit.
The announcement comes a year after New Mexico's attorney general told the company that the state intended to file an action against Vivint and its officers. The company disclosed that notice in a regulatory filing last March.
Residential solar companies have faced criticism in recent years for aggressive sales tactics that contributed to a fall in adoption of rooftop solar last year.
In the complaint, the state said Vivint's contract, known as a power purchase agreement, "hooks consumers into paying more for energy, entangles consumers' property rights, and ensnares consumers with a twenty-year contract."
It alleges that Vivint, which signs up customers through door-to-door solicitations, makes inaccurate promises about the cost savings provided by its solar systems and misleading claims about the power and rates provided by utilities.
It also says Vivint's practice of filing financial statements called "fixture filings" that list it as a secured party on a home's title creates confusion when a homeowner tries to sell or refinance the property.
The lawsuit was filed in New Mexico state court in Bernalillo County.
Vivint, which is based in Lehi, Utah, said it could not comment specifically on the pending litigation.
"Our commitment to our customers is to provide them the opportunity to adopt clean, renewable energy while always adhering to the highest ethical sales standards. We believe we have honored this commitment in New Mexico and that our practices in the state comply with applicable law," the company said in an emailed statement. (Reporting by Nichola Groom in Los Angeles Editing by Matthew Lewis)