Chemical Safety Incidents
AZ Solar Plant Air Quality Fine
Thursday, September 29, 2016 @ 04:09 PM gHale
The Solana Generating Station west of Gila Bend, AZ, will pay $1.5 million in fines for air-quality violations that date back to 2014, said officials at the Maricopa County Air Quality Department.
Solana is a concentrating solar plant that uses large, curved mirrors to focus sunlight on tubes of oil. The hot oil is able to make steam and spin turbines, generating about 250 megawatts of electricity.
The department said the plant’s 21 air-quality violations include exceeding the pollution levels allowed by its permits, failure to conduct performance tests as required and removing an emissions control system without approval.
Abengoa of Spain built the plant through an American subsidiary with a $1.45 billion federal loan and about $550 million in additional capital. The plant sells all of its electricity to Arizona Public Service Co. and the money from those sales ends up used to repay the federal loan.
That amount of power is enough to serve about 62,000 homes at once, and Solana can continue to make electricity for six hours past sunset by storing some of the heat.
The $1.5 million settlement shows equipment used to control oxides of nitrogen from releasing to the atmosphere from the heating of molten salt suffered damage in November 2014 and the plant did not complete a required test to show it was functioning, according to records obtained by The Arizona Republic.
They also show the plant exceeded the amount of water it was permitted to run through its cooling towers in the first half of 2015, and the company self-reported the violation.
The company also reported in 2014 it had exceeded the emission limit for its heat-transfer fluid for the preceding 12 months by releasing 8,512 pounds of the fluid, 32 pounds more than its permit allowed.
“This settlement and the associated fine reflect the significance of their air pollution violations,” said Maricopa County Air Quality Department Director Philip McNeely. “We are pleased that Arizona Solar One is taking positive steps to improve their operation. This company has indicated their willingness to work with the department to ensure that future renewable energy production at this facility complies with all appropriate air quality regulations.”
These issues follow previous troubles with the plant with the fluid, described as Terminol VP-1 in previous Maricopa County reports. In November 2014, the mildly toxic fluid was leaking from tanks, forming a small stream flowing into an open retention basin, according to the inspection report. The chemical can cause eye, skin and respiratory irritation and can cause serious injury if inhaled in sufficient quantities.
Inspector Joseph Zumello reported at the time he could smell heat-transfer fluid throughout the site and observed it leaking from joints in the piping. He also wrote that a heat exchanger had over-pressurized and exploded before the inspection.
In May 2014, the department received a citizen complaint of a “burning plastic” smell coming from the plant.