How about an interactive website where they can calculate their own SAVINGS (the savings they WOULD get if they signed up with you).

Just acouple of inputs -- amount of electricity you use per month -- how much per [unit -- KWH?] are they now paying, etc.

Then your selling could be leaving voicemail messages that say, "We save the typical biz [$XXX.XX] per month -- I'm not sure if we can save you money too... but you can easily find out for yourself just by looking at our website: [whatever].com. It'll take just 3 minutes to see if we can save you hundreds of dollars a month. If you have any questions, my name + number are: [whatever].

-- TW