Preliminary engineering analysis for clothes washers

The Engineering Analysis provides information on efficiencies, manufacturer costs, and other characteristics of the appliance class being analyzed. For clothes washers, there are two classes: standard and compact. Since data were not available to analyze the compact class, only clothes washers were analyzed in this report. For this analysis, individual design options were combined and ordered in a manner that resulted in the lowest cumulative cost/savings ratio. The cost/savings ratio is the increase in manufacturer cost for a design option divided by the reduction in operating costs due to fuel and water savings

Feasibility of Using Measurements of Internal Components ofTankless Water Heaters for Field Monitoring of Energy and Water Use

The objective of this study was to determine if it was feasible to collect information regarding energy use and hot water delivery from tankless gas water heaters using the sensors and controls built into the water heaters. This could then be used to determine the water heater efficiency ? the ratio of energy out (hot water delivered) to energy in (energy in the gas) in actual residential installations. The goal was to be as unobtrusive as possible, and to avoid invalidating warranties or exposing researchers to liability issues. If feasible this approach would reduce the costs of instrumentation.This paper describes the limited field and laboratory investigations to determine if using the sensors and controls built into tankless water heaters is feasible for field monitoring.It was more complicated to use the existing gas flow, water and temperature sensors than was anticipated. To get the signals from the existing sensors and controls is difficult and may involve making changes that would invalidate manufacturer warrantees. The procedures and methods for using signals from the existing gas valves, water flow meters and temperature sensors will vary by model. To be able to monitor different models and brands would require detailed information about each model and brand.Based on these findings, we believe that for field monitoring projects it would be easier, quicker and safer to connect external meters to measure the same parameters rather than using the sensors and controls built into tankless water heaters

U.S. Building-Sector Energy Efficiency Potential

This paper presents an estimate of the potential for energy efficiency improvements in the U.S. building sector by 2030. The analysis uses the Energy Information Administration's AEO 2007 Reference Case as a business-as-usual (BAU) scenario, and applies percentage savings estimates by end use drawn from several prior efficiency potential studies. These prior studies include the U.S. Department of Energy's Scenarios for a Clean Energy Future (CEF) study and a recent study of natural gas savings potential in New York state. For a few end uses for which savings estimates are not readily available, the LBNL study team compiled technical data to estimate savings percentages and costs of conserved energy. The analysis shows that for electricity use in buildings, approximately one-third of the BAU consumption can be saved at a cost of conserved energy of 2.7 cents/kWh (all values in 2007 dollars), while for natural gas approximately the same percentage savings is possible at a cost of between 2.5 and 6.9 $/million Btu. This cost-effective level of savings results in national annual energy bill savings in 2030 of nearly$170 billion. To achieve these savings, the cumulative capital investment needed between 2010 and 2030 is about $440 billion, which translates to a 2-1/2 year simple payback period, or savings over the life of the measures that are nearly 3.5 times larger than the investment required (i.e., a benefit-cost ratio of 3.5)

Saving Water Saves Energy

Hot water use in households, for showers and baths as wellas for washing clothes and dishes, is a major driver of household energyconsumption. Other household uses of water (such as irrigatinglandscaping) require additional energy in other sectors to transport andtreat the water before use, and to treat wastewater. In California, 19percent of total electricity for all sectors combined and 32 percent ofnatural gas consumption is related to water. There is a criticalinterdependence between energy and water systems: thermal power plantsrequire cooling water, and water pumping and treatment require energy.Energy efficiency can be increased by a number of means, includingmore-efficient appliances (e.g., clothes washers or dishwashers that useless total water and less heated water), water-conserving plumbingfixtures and fittings (e.g., showerheads, faucets, toilets) and changesin consumer behavior (e.g., lower temperature set points for storagewater heaters, shorter showers). Water- and energy-conserving activitiescan help offset the stress imposed on limited water (and energy) suppliesfrom increasing population in some areas, particularly in drought years,or increased consumption (e.g., some new shower systems) as a result ofincreased wealth. This paper explores the connections between householdwater use and energy, and suggests options for increased efficiencies inboth individual technologies and systems. Studies indicate that urbanwater use can be reduced cost-effectively by up to 30 percent withcommercially available products. The energy savings associated with watersavings may represent a large additional and largely untappedcost-effective opportunity

Wooden box-type windows in Vienna - still up to date? An analysis taking into account economic, legal, technical and historical aspects

Die historisch verbauten Holzkastenfenster sind von wesentlicher Bedeutung für die Funktionalität und für das Erscheinungsbild vieler Gebäude in Wien und prägen das Stadtbild im Altbestand. Die Arbeit stellt eine ganzheitliche Betrachtung von Holzkastenfenstern im Vergleich zu Isolierglasfenstersystemen unter Berücksichtigung der Nachhaltigkeit und der Klimaziele 2050 dar. Hierbei werden wirtschaftliche und technische Faktoren wie Investitionskosten, technische Spezifikationen, öffentliche Förderungen, steuer- und bestandsrechtliche Bestimmungen sowie Bewertungsfragen der Immobilie untersucht.Kastenfenster werden oftmals nicht nach ihrem Lebenszyklus beurteilt, sondern in einer Momentaufnahme mit Isolierglassystemen verglichen. Das technische System Holzkastenfenster unterscheidet sich wesentlich von Fenstern mit nur einer Ebene.Holzkastenfenster sind langlebig und bestehen häufig seit über 100 Jahren. Demgegenüber sind Holzkastenfenster aufgrund der zwei Fensterebenen aufwändig in der Reinigung und in der Wartung, was aufgrund der bestandsrechtlichen Bestimmungen der unterschiedlichen Zuständigkeit von Eigentümer und Nutzer für die Außen- und der Innenebene zusätzlich erschwert wird. Die beiden Fensterebenen funktionieren jedoch bauphysikalisch nur zusammen. Die Verbesserungsmöglichkeiten von Holzkastenfenstern hinsichtlich Wärmeschutz und Sonnenschutz sind sehr vielfältig. Die Wirkungsweise und Performance dieser Fensterart wird laufend erforscht. Neue technische Innovationen wie z.B. das Vakuumisolierglas können dazu beitragen, bestehende Fenster im Einklang mit den Klimazielen thermisch zu verbessern. In der Wirtschaftlichkeitsrechnung kann gezeigt werden, dass Holzkastenfenster ohne thermische Ertüchtigung auf Basis einer dauerhaften Energiepreiserhöhung von 7% p.a. gegenüber Kunststoffisolierglasfenstern gleichwertig sind.Bei Erwartung höherer, dauerhafter Energiepreissteigerungen ist eine thermische Ertüchtigung vorzuziehen. Aus heutiger Sicht ist der Erhalt von Holzkastenfenstern einezeitgemäße, nachhaltige und langfristig wirtschaftliche Alternative zum Fenstertausch und ist darüber hinaus aus architektonischer und kulturhistorischer Sicht erstrebenswert