OpEx (Operational Expenditure)

“OpEx” (also “OPEX” and “opex”) stands for “operational expenditure” or “operational expense” or “operating expenditure” or “operating expense.” “CapEx” stands for “capital expenditure” or “capital expense.” OpEx is the regular expense for running operations; CapEx is the irregular expense for capital improvements.
 
Both “OpEx” and “CapEx” have been cited in print since at least 1987.
 
 
Wikipedia: Operating expense
An operating expense, operating expenditure, operational expense, operational expenditure or OPEX is an ongoing cost for running a product, business, or system. Its counterpart, a capital expenditure (CAPEX), is the cost of developing or providing non-consumable parts for the product or system. For example, the purchase of a photocopier involves CAPEX, and the annual paper, toner, power and maintenance costs represents OPEX. For larger systems like businesses, OPEX may also include the cost of workers and facility expenses such as rent and utilities.
 
In business, an operating expense is a day-to-day expense such as sales and administration, or research & development, as opposed to production, costs, and pricing. In short, this is the money the business spends in order to turn inventory into throughput.
 
On an income statement, “operating expenses” is the sum of a business’s operating expenses for a period of time, such as a month or year.
 
In throughput accounting, the cost accounting aspect of the theory of constraints (TOC), operating expense is the money spent turning inventory into throughput. In TOC, operating expense is limited to costs that vary strictly with the quantity produced, like raw materials and purchased components. Everything else is a fixed cost, including labour (unless there is a regular and significant chance that workers will not work a full-time week when they report on its first day).
 
Google Books
Modular Subsea Production Systems
By Society for Underwater Technology (SUT)
London: Graham & Trotman Limited
1987
Pg. 147:
The merits of each combination will then be assessed against several economic criteria which will involve consideration of capex, opex, expenditure phasing, availability etc., but also a judgement (often subjective) will be made as to the technical risk.
 
Google Books
Reliability Achievement: The Commercial Incentive:
Proceedings of the 10th Annual Symposium of the Society of Reliability engineers, Scandinavian Chapter, held at Stavanger, Norway, 9-11 October 1989
By Terje Aven; Society of Reliability Engineers. Scandinavian Chapter. Symposium
London: Elsevier Applied Science
1989
Pg. 3:
capital expenditures (capex)
operational expenditures (opex)
(...)
The main cost elements considered in Troll life cycle cost evaluations are: capital expenditures (capex) operational expenditures (opex) production output.
 
OCLC WorldCat record
Surveying to Reduce the Capex and Opex of Subsea Operations
Author: C Mott
Edition/Format:   Article : English
Publication: SPECIAL PUBLICATION- HYDROGRAPHIC SOCIETY, 37, (1997): 5
Database: British Library Serials
 
OCLC WorldCat record
Subsea pig launcher option - Machar deployment, like other applications on marginal or deepwater fields, rationalizes CAPEX, OPEX costs.
Publisher: Tulsa, OK : PennWell Company, 1993-
Edition/Format:   Article : English
Publication: Offshore. 58, no. 4, (1998): 112
Database: ArticleFirst
 
Oil & Gas Journal
Iranian options most economically viable for exporting Caspian oil
03/17/2003
(...)
Oil pipeline costs include three categories: Capital expenditures (Capex), operating expenditures (Opex), and host country expenditures.
 
OCLC WorldCat record
Reduced capex reflected in higher opex
Edition/Format:   Article : English
Publication: TELECOM MARKETS, no. 453, (June 3, 2003): 5
Database: British Library Serials