Last year,San Francisco voters overwhelmingly approved a $100-million bond initiative to pay for solar panels,wind power and energy efficiency for public buildings.

• 去年，旧金山的选民以压倒性优势通过了一项发行1亿美元债券的倡议，来偿付太阳能电池板、风能及提高公共建筑中能源利用效率所需的费用。