or any subsidies available. , General Motors combined sales of plug-in electric vehicles in the U.S. totaled almost 197,000 units and are expected to pass 200,000 early in 2019. Thereafter, the applicable tax credit reduces gradually until it is completely phased out beginning on January 1, 2020. The price for the home charging units is plus installation costs. The Voltec is a home-charging unit built by SPX for Volt owners. It is a 240V AC charger, and, according to General Motors, can replenish the Volt's batteries in about four hours. Consumer Reports has advised buyers to budget up to , as many older homes may need a substantial electrical upgrade because the U.S. National Electrical Code requires that the charger have its own dedicated 240-volt, 30-amp circuit. Early buyers can benefit from the federal tax credit available for charging equipment. The 2011 Volt was not submitted for application to the California Air Resources Board's (CARB) Clean Vehicle Rebate Project rebate and therefore was not required to meet the 10-year battery warranty requirement for enhanced advanced technology partial zero-emissions vehicles (enhAT-PZEV). The Volt team explained that for the launch General Motors decided to go with a common national package that includes an 8-year battery warranty. For this reason owners of the 2011 Volt did not qualify for California's rebates and free access to use carpool lanes even when traveling solo. A third package, scheduled for 2013, is under development with an E85 flex-fuel engine. General Motors engineering team commented that "introducing two or three packages of an entirely new technology set and platform at the same time wasn't an option." In February 2012 General Motors began deliveries of a low emission version destined for California that features a new low emissions package that allows the 2012 Chevrolet Volt to qualify as an enhanced, advanced technology –partial zero emissions vehicle (enhAT-PZEV) and have access to California's high-occupancy vehicle lanes (HOV). The new standard California version of the Volt features a modified engine and exhaust components. The catalytic converter was modified to add a secondary air-injection pump that "streams ambient air into the exhaust stream to increase its ability to remove pollutants." Owners of a 2012 Volt with the low emissions package are eligible to apply for one of 40,000 available HOV lane stickers issued to vehicles that qualify as a California AT-PZEV. The permits are handed out on a first-apply, first-served basis.