Monetary capital is the money required to acquire and construct long-term assets (capital assets) necessary to safely and reliably operate an electric or natural gas delivery system. Capital needs may be funded from a variety of resources including debt, equity, and retained earnings. Companies often need to raise capital to finance regular business operations as well as business expansions.

An additional type of capital required to run an energy company is working capital, which is the amount of “cash on hand” a firm needs to pay its bills during the time between when money is spent on capital and expenses, and when revenue is collected from customers. 

Utilities and other energy companies are considered capital-intensive, meaning that they require substantial amounts of capital each year to finance operations. It is common for a large utility to have annual capital expenditures in excess of $1 billion. This is in addition to the utility's day-to-day recurring costs of doing business.