How do you label
Time= energy • power

First of all, that equation is not correct, which may be the reason that you're having trouble assigning units to the quantities.Power is defined as [energy / time],  so  [Energy] = [ power x time ],and         [Time] = [ energy / power ].Unit-wise, these equations are correct just as they appear here, with no proportionality constants or conversion factors, when ...[ Power ] = watts[ Energy ] = joules[ Time ] = seconds .