Professional Residential Solar Bid Analysis

I mentioned in an earlier post that I'd been disappointed by the bids I'd received from three of our local professional solar firms.  Now that I've gone over the various layouts and configurations it might be interesting to examine those bids and see how they stack up.

Bid #1 provided pretty good detail.  Bid #2 just provided a bottom-line number.  Bid #3 was essentially given by phone.  And 'My Est' was based on prices for components I could purchase as an individual (mostly from from Wholesale Solar) plus estimated labor by an electrician.  (The companies providing bids will not be identified.)

                      Bid #1    Bid #2    Bid #3    My Est
------------------  --------  --------  --------  --------
Total Wattage          5,250     4,800     4,800     8,400
Panels Total        $ 28,673                      $ 34,440
  Each                 $ 956                         $ 861
  Type            Solarworld     Sanyo       REC     Sanyo
  Wattage Ea.            175       200       200       210
  Count                   30        24        24        40
Inverters Total      $ 6,213                       $ 7,070
  Each                 $ 207                       $ 3,535
  Type               Enphase   Enphase   Enphase Sunny Boy
  Count                   30        24        24         2
Racking Total        $ 3,784                       $ 2,218
Labor Total          $ 2,870                      $ ~3,000
System Discount          $ 0       $ 0       $ 0  $ -3,269
------------------  --------  --------  --------  --------
Grant Total $       $ 41,541  $ 40,870  $ 38,040  $ 43,459
Cost per Watt         $ 7.91    $ 8.51    $ 7.93    $ 5.17

------------------  --------  --------  --------  --------
Federal Tax Credit  $ 12,462  $ 12,261  $ 11,412  $ 13,078
Net System Cost     $ 29,079  $ 28,609  $ 26,628  $ 30,381
Effective per Watt    $ 5.54    $ 5.96    $ 5.55    $ 3.62

For comparison purposes, at the time of writing this blog entry, the prices for various components from Wholesale Solar are as follows:

  Solarworld 175 W panels         $ 855
  Sanyo 200 W panels                N/A
  REC Solar 205 W panels          $ 564
  Enphase 175 W microinverters    $ 197
  Enphase 205 W microinverters      N/A

Doing the work myself (hiring out the electrical expertise and roof labor, of course) has a distinct advantage in terms of price per watt.

For only 4% more money I can get 60% more electrons!

It was pretty easy for me to make a decision: I'll be my own solar contractor and work with an electrician.