Frederick County plans to replace about 21% of its vehicle fleet with electric vehicles, as well as use biodiesel fuel for other parts of the fleet, to help lower the county’s greenhouse gas emissions. At Mobilize Frederick’s climate summit at Hood College on Friday, County Executive Jessica Fitzwater announced a plan to replace parts of the county fleet with electric vehicles (EVs), as well as a resource document and website for residents and businesses to consult when considering switching to EVs.