[The Tribune] By 2020 more than half of the new single family homes built in San Luis Obispo must have solar power ability, the City Council decided Tuesday. The Council made the decision as it began the grueling process of updating and combing policies on open space, and energy and resource conservation. Unable to finish reviewing policy changes in a single meeting, Council members opted to continue the discussion during their March 21 meeting. The changes to solar requirements drew some concerns from Council members who worried it may be too specific of a guideline for a general overview policy, rather than an ordinance. Under the policy, 5 percent of all new single family homes built in 2008 must include solar panels. The percentage will jump by 4 percent of new homes built every year until 2020.