An economic and environmental assessment of transporting bulk energy from a grazing ocean thermal energy conversion facility

Elisabeth A. Gilmore, Andrew Blohm and Steven Sinsabaugh

Renewable Energy, 2014, vol. 71, issue C, 361-367

Abstract: An ocean thermal energy conversion (OTEC) facility produces electrical power without generating carbon dioxide (CO2) by using the temperature differential between the reservoir of cold water at greater depths and the shallow mixed layer on the ocean surface. As some of the best sites are located far from shore, one option is to ship a high-energy carrier by tanker from these open-ocean or “grazing” OTEC platforms. We evaluate the economics and environmental attributes of producing and transporting energy using ammonia (NH3), liquid hydrogen (LH2) and methanol (CH3OH). For each carrier, we develop transportation pathways that include onboard production, transport via tanker, onshore conversion and delivery to market. We then calculate the difference between the market price and the variable cost for generating the product using the OTEC platform without and with a price on CO2 emissions. Finally, we compare the difference in prices to the capital cost of the OTEC platform and onboard synthesis equipment. For all pathways, the variable cost is lower than the market price, although this difference is insufficient to recover the entire capital costs for a first of a kind OTEC platform. With an onboard synthesis efficiency of 75%, we recover 5%, 25% and 45% of the capital and fixed costs for LH2, CH3OH and NH3, respectively. Improving the capital costs of the OTEC platform by up to 25% and adding present estimates for the damages from CO2 do not alter these conclusions. The near-term potential for the grazing OTEC platform is limited in existing markets. In the longer term, lower capital costs combined with improvements in onboard synthesis costs and efficiency as well as increases in CO2 damages may allow the products from OTEC platforms to enter into markets.

Keywords: Ocean thermal energy conversion (OTEC); Ammonia; Liquid hydrogen; Methanol; Onboard synthesis; Market analysis (search for similar items in EconPapers)
Date: 2014
References: View references in EconPapers View complete reference list from CitEc
Citations: View citations in EconPapers (2)

Downloads: (external link)
http://www.sciencedirect.com/science/article/pii/S0960148114002729
Full text for ScienceDirect subscribers only

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:eee:renene:v:71:y:2014:i:c:p:361-367

DOI: 10.1016/j.renene.2014.05.021

Access Statistics for this article

Renewable Energy is currently edited by Soteris A. Kalogirou and Paul Christodoulides

More articles in Renewable Energy from Elsevier
Bibliographic data for series maintained by Catherine Liu ().