The purpose of this paper is to study a Monte Carlo simulation of the discounted payback, and its application to investment appraisal. The underlying project in the case study has a useful life of 10 years with an initial outlay of $2,000, and with stochastic, independent, and normally distributed cash inflows. These cash inflows are simulated from the same normal frequency distribution, i.e. f...

The paper presents the results of two full-scale applications of the anaerobic co-digestion process of waste activated sludge together with the organic fraction of municipal solid wastes. The experiences were carried out at Viareggio and Treviso wastewater treatment plants (Italy). In the first plant, 3 tons per day of source sorted OFMSW were co-digested with waste activated sludge, increasing...

All-organic-based photovoltaic solar cells have attracted considerable attention because of their low-cost processing and short energy payback time. In such systems the primary dissociation of an optical excitation into a pair of photocarriers has been recently shown to be extremely rapid and efficient, but the physical reason for this remains unclear. Here, two-dimensional photocurrent excitat...

The development and rapid consumer adoption of energy efficiency products and renewable energy systems are key elements of UK and EU carbon reduction strategies to meet the challenge of climate change. Many such technologies are available for domestic use, but despite government incentives to meet carbon reduction targets consumer adoption has been slow. This Open University research with 111 i...

Variable speed, variable frequency drives are a common "no-brainer" application to improve energy efficiency. However, on pumps in open systems with a significant static head, the energy savings can be much less than a shortcut application of the affinity laws would indicate. Indeed, in some cases in the authors' experience, VFDs have been found to actually use more energy. This paper discusses...

1. F-Chart Method 1.1. Performance and Design of Liquid-Based Solar Heating Systems 1.1.1. Storage Capacity Correction 1.1.2. Collector Flow Rate Correction 1.1.3. Load Heat Exchanger Size Correction 1.2. Performance and Design of Air-Based Solar Heating Systems 1.2.1. Pebble Bed Storage Size Correction 1.2.2. Air Flow Rate Correction 1.3. Performance and Design of Solar Service Water Systems 1...

In this paper, a novel integrated system is proposed to improve the performance of a conventional low-grade geothermal-based organic Rankine cycle (ORC). The main idea is to utilize two TEG units to recover the waste heat of the condenser and geothermal brine. The proposed model is investigated and compared with simple ORC from the energy, exergy, and exergoeconomic viewpoints through the param...

In this article, we describe details of the data used in the research paper "Confidence bounds for energy conservation in electric motors: An economical solution using statistical techniques" [1]. The data presented in this paper is intended to show benefits of high efficiency electric motors over the standard efficiency motors of similar rating in the industrial sector of Pakistan. We explain ...