The plan is designed to use energy bill savings from efficiency upgrades to cover the annual payments on a $3.7 million bond the City Council approved in August 2013 .
Efficiency upgrades city Auditor Thomas Kelly estimated last month to be about $298,000 in the first year .
The plan is designed to use energy bill savings from efficiency upgrades , which city Auditor Thomas Kelly estimated last month to be about $298,000 in the first year , to cover the annual payments on a $3.7 million bond the City Council approved in August 2013 .