SEATTLE (AP) — Seattle Mayor Jenny Durkan says Seattle will no longer use fossil fuels like natural gas to heat, cool and cook in new and substantially altered city-owned buildings and will come up with a plan by 2021 to transition all city-owned buildings to clean electric systems over time. Durkan included those directives in a “Green New Deal” executive order Wednesday. Neither the new KeyArena nor the Seattle Aquarium expansion pavilion planned for construction will be covered by the city’s new fossil-fuel ban, however, because the projects are underway. Both will be included in the city’s longer-term electrification plans. There’s no deadline yet for all city buildings to be fossil-fuel free.