Simple model for prediction of loads in district-heating systems

In order to improve the operation of district-heating systems, it is necessary for the energy companies to have reliable optimization routines, both computerized and manual, implemented in their organizations. However, before a production plan for the heat-producing units can be constructed, a prediction of the heat demand first needs to be determined. The outdoor temperature, together with the social behaviour of the consumers, have the greatest influence on the demand. This is also the core of the load prediction model developed in this paper. Several methodologies have been proposed for heat-load forecasting, but due to lack in measured data and due to the uncertainties that are present in the weather forecasts, many of them will fail in practice. In such situations, a more simple model may give as good predictions as an advanced one. This is also the experience from the applications analyzed in this paper.Heat-load forecasting District heating Linear least squares

Greenhouse gas emissions from power generation and consumption in a nordic perspective

During the last decade, there has been an intensive debate on-going in Sweden about how power generation and use affect global warming. More precisely, the discussion has considered how electricity shall be assessed from an environmental and climate perspective in different situations. This article gives a critical analysis on the main viewpoints. A number of environmental-impact assessment principles are outlined and critically examined. Concepts like average electricity and marginal electricity are discussed, and Electricity Disclosure as a basis for evaluation is addressed. The impact from Emission Trading and Tradable Green Certificates is also considered. Recommendations to concerned stakeholders are given. The clash points in the Swedish debate are highlighted and thus made available to a broader audience outside Scandinavia.Marginal electricity Electricity disclosure Environmental-impact assessment

An energy efficiency program for Swedish industrial small- and medium-sized enterprises

Industrial energy programs such as energy audit programs and long-term agreements (LTAs) are one of the most common means of promoting energy efficiency in industry. As a result of the European Energy End-Use Efficiency and Energy Services Directive from 2006, the Swedish Government Bill proposed a national energy program towards industrial small- and medium-sized enterprises (SMEs) using more than 500 MWh energy annually. The aim of this paper is to present the structure and design of the program, adopted in 2010, the logics in brief behind the structure, as well as an ex-ante evaluation of the programs cost-effectiveness. The paper is aimed towards the part of the program involving industry, i.e. not the part involving companies within service and sales etc. The proposed design primarily includes a subsidized energy audit with some minor LTA-elements, such as the need to report results from the energy audit, to present a plan over which measures to conduct, and after three years present which measures that were implemented. The ex-ante evaluation of the program shows a cost-effectiveness of 0.25-0.50 Eurocents/kWh, yielding savings of about 700-1 400 GWh annually.Original Publication:Patrik Thollander and Erik Dotzauer, An energy efficiency program for Swedish industrial small- and medium-sized enterprises, 2010, JOURNAL OF CLEANER PRODUCTION, (18), 13, 1339-1346.http://dx.doi.org/10.1016/j.jclepro.2010.04.020Copyright: Elsevier Science B.V., Amsterdam.http://www.elsevier.com