Given the high familiarity with the VA scheme, companies that apply for entering a
VA are usually economically motivated to do so. The decision to apply has normally
been preceded by a rough cost-benefit analysis. For many companies, the
main benefit of signing a VA is the CO2 tax rebate. For some companies the CO2
tax rebate is of such considerable size that the VAs are perceived as necessary
rather than voluntary. Table 1 shows the size distribution of the annual CO2 tax rebate
payments in 2003. Another important driver for the VAs is the reduction of
energy costs resulting from the energy efficiency measures.