Capacity market in Japan currently determines VoLL (Value of Lost Load) substantially and uniformly using reference procurement cost and target supply reliability, and can be regarded to be derived from a supplier's perspective. However, as seen in transactions of demand response (DR) in power markets, compensations of demand adjustment vary among DR suppliers. Therefore, deriving VoLL from customers' perspectives shall be more in line with reality.

This paper proposes a unique method to quantitatively assume VoLL of 12 industries based on revealed preference approach using actual energy consumption data of customers of each industries. This paper also proposes a new method to economically determine the amount of capacity procurement and the different levels of supply reliability of each customers, considering the variation of VoLL among customers and also the congestions of interconnectors.

Clarifying the supply reliability of customers not only encourages them to proactively introduce measures, but is also effective for paradigm changing to secure stable power supply reflecting both supplier and customer perspectives.