Comments for Colorado PUC

     The Colorado Public Utilities Commission will be accepting comments from any citizen on the proposed rules for Community Solar Gardens (HR1342).  Comments submitted on or before October 22 will be considered when deciding the structure of the proposed rules.  Please email info@solargardens.org with your suggestions.

     The Solar Gardens Institute is gathering together comments from interested people in order to propose the best rules possible.  Here is a skeleton of what we will be offering:


Allocation of slots under 6MW cap- the program will likely be oversubscribed.  How to fairly allocate shares to promote community initiated projects

1. A 1.5 MW cut-out for systems 100kW or smaller (likely corresponding with a tier in XCEL’s standard offer).  This would make the overall allocation look something like: ( 1.5MW 10-100k; 1.5MW 101-500k; 3MW 501k+ )

2. Require groups applying to have interested subscribers, to be an established community group, or to qualify as a "community based project" to reduce simple speculation

3. Require geographic diversity of solar gardens – make sure each county gets some kind of allocation

4. Use a modified lottery rather than first-come-first-served

5. A way to give preference to systems that include low income, renters, or agricultural systems, as specified in HR1342.  This could include:

a) A requirement that 1/3 of the systems primarily support one of these categories
–or-
b) A requirement that each system support at least 1/3 of subscribers from these categories

Aggregate metering – allow a subscriber to apply a solar garden share to multiple meters

    1.  An institution that purchases solar garden shares may apply these to multiple meters, by virtual net metering against the total number of the meters.


Address outcome of program failure – natural disaster, business failure, low production, no subscribers, etc.

1. If an array is not built within a specified period of time, the slot under the 6MW cap will be re-opened and given to the next slot on a waiting list

2. The PUC should allow for the sale or decommissioning of a solar garden and re-opening of its allocation if the subscriber organization fails

3. Insurance should provide the replacement value of an array if it is destroyed in a fire or other disaster

Should “proportional interest” include leasing or PPA models, or only ownership of the panels?  How will this affect low income subscribers?

1. For the purposes of implementation, “proportional interest” may include leases   where ownership can be transferred to the subscriber.

2. “Proportional interest” may include arrangements where the panels are owned in trust for a given subscriber group


Solar Gardens for Multiple Roofs – Segmented Arrays

     Condominium complexes, business parks, home owners associations, and many other potential solar sites have a number rooftops with good solar access.  As an example, see the Hayes Valley affordable housing site in San Francisco: http://www.novoco.com/journal/2010/03/news_retc_201003.php - notice the photographs of arrays on adjacent buildings.  These arrays may tie into the grid at different meters, which might be located on different parcels.  This kind of installation is ideal for grid-tied micro-inverters, which have a flat cost at any degree of granularity. 

     Industrial parks are ideal places for ground mounted installations that might be linked together.  These sites are typically subdivided into multiple parcels, so a single solar garden might be installed on several of these.  The rules should be flexible enough to accommodate this configuration.

     What if the segments are geographically dispersed, say on the various roofs of a school district?  This is a good thing!  Check out this recent report from Lawrence Berkeley Labs that shows how this “smoothes out” the total power available to the grid on a minute-to-minute basis:  http://eetd.lbl.gov/ea/ems/reports/lbnl-3884e.pdf

     For these reasons the rules should allow a solar garden to be segmented into multiple parts, on parcels throughout a county or municipality.