What is the fuel source?
Is fuel source predetermined, or will it be selected to meet overall targets/goals?
What is the ecological impact of the chosen fuel source? Does this align with other project goals ( GHG emissions, ecological impacts)?
What is the local/regional primary energy source(s) for grid power (electricity) or distributed energy (natural gas)? What are the environmental consequences of this energy? What efficiency factor does the local grid/distribution utility have?
What is the equipment efficiency?
Has the efficiency rating of specific equipment choices been factored into overall efficiency rating?
Are there significant efficiency differences among competitors within the equipment range?
What is the service life of equipment?
Does the equipment have a warranty and/or an expected service life?
Has replacement cost been factored into the overall cost of the system?
What is the maintenance schedule and ease of use of the system?
Is fuel input automated? To what degree? For example, a wood stove requires manual refueling every 2-4 hours; a pellet stove can require refueling daily, weekly, monthly, or seasonally depending on the size of the hopper; a natural gas appliance doesn’t require any input from the homeowner.
What is the recommended maintenance schedule for the equipment (burners, filters, duct cleaning,)?
What is the control system for the equipment (central thermostat, room-by-room thermostat, no thermostat) and how easy is it to understand and use effectively?
What equipment other than heating/cooling appliances will be used?
What are the ventilation requirements (by code and/or by choice) and how will the ventilation system impact efficiency?
How do choices regarding refrigeration, cooking, washing, lighting, bathing, and entertainment appliances affect overall energy efficiency?
Will lifestyle choices support energy efficiency targets?
Are use patterns consistent with efficiency targets?
Has an honest and accurate energy audit been performed.