We recognize that data collection can be challenging for voluntary programs. However, 8 of the 11 programs in our review showed weaknesses in their current data collection and reporting systems – caused by limited, unverified, and anonymous data reporting. These systems are neither transparent nor verifiable, and are limited by anonymous reporting and use of third party industry data. Further, none of the programs' memoranda of understanding establish consequences for failure to report, and generally provided little assurance that firms are actively participating in the program. EPA has been a leader in developing protocols to produce estimates for greenhouse gas sources and sinks categories in the United States. However, data uncertainty has continued to be a concern the voluntary programs have struggled to address. As a result, the reported accomplishments of these voluntary programs may be based on unreliable data.
Voluntary greenhouse gas reduction programs have limited potential
The set of voluntary GHG programs we reviewed use outreach efforts to recruit program partners and reduce GHG emissions. We found the greatest barriers to participation were the perceived emission reduction costs and reporting requirements. We also found that it is unlikely these voluntary programs can reduce more than 19 percent of the projected 2010 GHG emissions for their industry sectors. From this, we determined that if EPA wishes to reduce GHG emissions beyond this point, it needs to consider additional policy options.