CARMA Notes: Corporate Data
As in previous releases, CARMA v3.0 includes information about the electricity production and emissions of corporate entities involved in power generation. Every plant in the CARMA database is assigned to a company. The vast majority of that information comes from a proprietary, commercial database underpinning CARMA. In some cases, corporate ownership of U.S. plants is also provided by data from the Department of Energy.
Power plant ownership is quite complicated, and there are often multiple layers of ownership between the immediate plant operator and the ultimate owner. CARMA attempts to report the ultimate owner whenever possible (i.e. the highest entity in the corporate hierarchy), relying largely on information from a private data supplier. When the parent company cannot be identified for a plant, the operating company (often a utility) is reported instead.
It must be stressed that maintaining accurate corporate information is extremely challenging. CARMA’s data suppliers are the best in the business, but even they cannot guarantee accuracy, especially outside North America where corporate hierarchies are less evident. There is also the problem that many large facilities are owned by multiple entities and it is not possible to track ownership shares worldwide. For all these reasons, the company data in CARMA should be considered a reasonable “best guess” of the primary entity ultimately responsible for ownership or operation of the plant.
For example, the generating units at the Scherer Plant in Juliette, Georgia (the largest CO2 emitter in the U.S.) are jointly owned to varying degrees by seven different corporate entities. Based on this information, one could reasonably consider Oglethorpe Power Corporation to be the primary owner. On the other hand, the plant is actually operated on a day-to-day basis by Georgia Power (also part owner), which is, in turn, a subsidiary of Southern Company – as is Gulf Power, also part owner of the plant. CARMA’s data suppliers, and hence the CARMA database, report the parent company as Southern Company. I use this example to illustrate the potential complexity of ownership arrangements and dispense the necessary “grain of salt”. To be fair, this is an especially complex case.
Although electricity and emissions data are available for multiple points in time (e.g. 2004, 2009, and the “Future”), the company assigned to each plant is based upon the most recent information available. For example, the CARMA v3.0 release in July, 2012 uses corporate ownership data thought to be current as of March, 2012. Notice that this makes company totals for earlier points in time (e.g. 2004 and 2009) possibly subject to error, since ownership could have been different at that time. The 2004 company totals for Southern Company, for example, are the aggregate 2004 electricity production and emissions of plants that Southern Company is currently listed as owning (not the plants they actually owned as of 2004). In general, the 2009 company totals are more likely to be accurate than 2004, especially in developing country power markets where changes are occurring rapidly.
CARMA also assigns a “Parent Country” to each company in the database. At present, this is based solely on an analysis of where the plurality of the company’s associated generating capacity is located. In the vast majority of cases, this yields an accurate result. If you come across exceptions, please contact me so I can rectify for future releases.
Finally, it is worth reiterating that CARMA’s company totals simply reflect emissions from associated power plants. Occasionally, one will find companies that have both power plants and other business activities. For example, major oil and gas companies like BP often own generators, and their operation is reflected as best as possible in CARMA’s company totals. But these figures do not reflect the full extent of CO2 or other greenhouse gas emissions from BP’s wider activities (drilling, refineries, pipelines, etc.).