Technologic, economic and exergoeconomic evaluation of proposed industrial heat and power plant revamp alternatives in an industrial company in Slovakia

Both European and Slovak legislation seek to promote efficient energetic media production with the support of old facilities, revamping being one of the embedded means. Based on our cooperation with Slovak industry, we analyzed several gas turbine based revamp alternatives of an industrial central heat and power plant of a paper mill in Slovakia from the technical, economic and exergoeconomic point of view, the latter being not yet applied in Slovakia to such a complex problem. The proposed alternatives exhibit a 45–55% marginal electric efficiency. However, at the given electric energy and natural gas prices and due to high fix production costs, individual project economics cannot ensure an attractive payback period unless providing ancillary services extensively. Overall and marginal results of the steam exergoeconomic costing procedure indicate that the proposed revamp alternatives are not able to provide cheaper electric energy than the existing configuration but they can produce cheaper low pressure steam for industry. The presented analysis provides a scheme and methodology for Slovak industry to properly cost the energetic media production.

Research highlights
► Proposed revamp solutions yield 45 to 55 marginal electric efficiency.
► High fix costs deteriorate the process economics.
► Exergoeconomic costing yields cheaper steam and more expensive electricity.
► Good project economics possible only with the AS provisioning at present.