Need Solar-v-Weatherization savings comparison graph

Hello all. I'm putting together a presentation on residential weatherization and would like to show a cost/benefit comparison between installing solar and weatherizing.  Has anyone seen a simple graphic showing this?  Thanks, Kris

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I don't know how simple this question is. There is data on weatherization outcomes available, but there are a lot of variables, such as region of the country, who's in charge of the money and the work, type of housing stock, etc. Solar is going to vary too, because of differences in how much the sun shines and how much utility power costs.
Weatherization is where to start. I dont have figures but look at the cost to supply 50% of the energy needs of an existing inefficient house using solar verus the cost to reduce demand by 50%.  It wont be close.

To show the importance of efficiency first, I used to use an example comparing light bulbs to a PV system, as follows. But solar lease options on the market have changed the game, making little to no capital outlay and instant energy offset for some systems in states with utility rebates. I know this doesn't exactly answer your question. But maybe it's worth a thought. Efficiency first is the right thing to do, but solar has it's place too.

Ten (10) 100-watt incandescent light bulbs x 10 hours/day = 10kWh/day (3650 kWh/year)
Ten (10 20-watt compact fluorescent bulbs x 10 hours/day = 2 kWh/day (730 kWh/year)
                      Difference: 2920 kWh/year

One 2,000-watt PV system x 1.45 (*Boulder Colorado -
                               2,900 kWh/year


        $50 for a light bulb vs. $5000 for the PV array*
                        What would you do?


Nice, Eric.  This is the sort of info I'm looking for.  I appreciate your input.  Thanks, Kris

Having worked in both PV installation field and being an energy auditor I would say that this should not be raised as a question of one VS the other, they should go hand-in-hand, weatherization preceeding solar installation.

Also I would suggest considering solar thermal before solar PV.

This Study posted on the Northwest Energy Star site may be helpful.  It has case studies for four or five homes approaching net zero.  they summarize the cost of reducing energy needs along with the costs of adding renewables.  It also does a fairly good job of summarizing issues we run into when taking energy efficiency to the next level.

Hope this helps.




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