A longitudinal study of informational interventions to save energy in an office building.
(1/98)
Informational interventions were employed to promote two behaviors relevant for efficient heating of individual offices in a large office building. In two successive winter seasons, interventions were applied during 4-week periods. Short-term effects were assessed weekly, and long-term effects were assessed 1 year after each of the two intervention periods. Improvements were observed in each intervention period, with partial behavior maintenance 1 year later. The changes observed in the individual offices across conditions are suggestive of the program's capacity to correct relapses in earlier proenvironmental behavior. (+info)
Healthy communities must also be sustainable communities.
(2/98)
The author contends that healthy communities must be both environmentally and socially sustainable, given that health depends on the quality of the built and natural environments, and that global change resulting from the industrial economy is affecting the web of life. He argues that suburban sprawl wastes scarce resources and disproportionately places those resources in the hands of suburban dwellers. Urban areas can be made more environmentally sustainable, especially with respect to energy consumption, which will help reduce air pollution and climate change and contribute in other ways to improved health. (+info)
Performance of an age series of alnus-cardamom plantations in the Sikkim Himalaya: productivity, energetics and efficiencies.
(3/98)
Biomass, net primary productivity, energetics and energy efficiencies were estimated in an age series of Alnus-cardamom plantations in the eastern Himalaya. The impact of stand age (5, 10, 15, 20, 30 and 40 years) on the performance of mixtures of N2-fixing (Alnus nepalensis) and non-N2-fixing (large cardamom) plants was studied. Large cardamom (Amomum subulatum) is the most important perennial cash crop in the region and is cultivated predominantly under Alnus trees. Net primary productivity was lowest (7 t ha(-1) per year) in the 40-year-old stand and was more than three times higher (22 t ha(-1) per year) in the 15-year-old stand. Agronomic yield of large cardamom peaked between 15 and 20 years of age. Cardamom productivity doubled from the 5- to the 15-year-old stand, and then decreased with plantation age to reach a minimum in the 40-year-old stand. Performance of cardamom in association of N2-fixing Alnus remained beneficial until 20 years of age. Annual net energy fixation was highest (444 x 10(6) kJ ha(-1) per year) in the 15-year-old stand, being 1.4 times that of the 5-year-old stand and 2.9-times that of the 40-year-old stand. Inverse relationships of production efficiency, energy conversion efficiency and energy utilized in N2-fixation against stand age, and a positive relationship between production efficiency and energy conversion efficiency suggest that the younger plantations are more productive. The Alnus-cardamom plantation system will be sustainable by adopting a rotational cycle of 15 to 20 years. (+info)
The public health benefits of insulation retrofits in existing housing in the United States.
(4/98)
BACKGROUND: Methodological limitations make it difficult to quantify the public health benefits of energy efficiency programs. To address this issue, we developed a risk-based model to estimate the health benefits associated with marginal energy usage reductions and applied the model to a hypothetical case study of insulation retrofits in single-family homes in the United States. METHODS: We modeled energy savings with a regression model that extrapolated findings from an energy simulation program. Reductions of fine particulate matter (PM2.5) emissions and particle precursors (SO2 and NOx) were quantified using fuel-specific emission factors and marginal electricity analyses. Estimates of population exposure per unit emissions, varying by location and source type, were extrapolated from past dispersion model runs. Concentration-response functions for morbidity and mortality from PM2.5 were derived from the epidemiological literature, and economic values were assigned to health outcomes based on willingness to pay studies. RESULTS: In total, the insulation retrofits would save 800 TBTU (8 x 10(14) British Thermal Units) per year across 46 million homes, resulting in 3,100 fewer tons of PM2.5, 100,000 fewer tons of NOx, and 190,000 fewer tons of SO2 per year. These emission reductions are associated with outcomes including 240 fewer deaths, 6,500 fewer asthma attacks, and 110,000 fewer restricted activity days per year. At a state level, the health benefits per unit energy savings vary by an order of magnitude, illustrating that multiple factors (including population patterns and energy sources) influence health benefit estimates. The health benefits correspond to 1.3 billion dollars per year in externalities averted, compared with 5.9 billion dollars per year in economic savings. CONCLUSION: In spite of significant uncertainties related to the interpretation of PM2.5 health effects and other dimensions of the model, our analysis demonstrates that a risk-based methodology is viable for national-level energy efficiency programs. (+info)
An enhanced rate-based emission trading program for NOX: the Dutch model.
(5/98)
Since 1997 government and industry in The Netherlands have been engaged in intensive policy discussions on how to design an emission trading program that would satisfy the Government's policy objectives within the national and international regulatory framework and accommodate industry's need for a flexible and cost-effective approach. Early on in the discussion the most promising solution was a rate-based approach, which dynamically allocated saleable emission credits based on a performance standard rate and actual energy used by facilities. All industrial facilities above a threshold of 20 MWth would be judged on their ability to meet this performance rate. Those "cleaner" than the standard can sell excess credits to others with an allocation that is less than their actual NOX emission. With some changes in law, such a design could be made to fit well into the national and EU legislative framework while at the same time uniquely meeting industry's requirement of flexibility toward economic growth and facility expansion. (An analysis of the legislative changes required will be given in a separate paper by Chris Dekkers.) However, the environmental outcome of such a system is not as certain as under an absolute emission cap. At the request of the Netherlands Ministry of Housing, Spatial Planning and the Environment (VROM), Automated Credit Exchange (ACE), in close cooperation with the working group of government and industry representatives introduced a number of features into the Dutch NOX program allowing full exploitation of market mechanisms while allowing intermediate adjustments in the performance standard rates. The design is geared toward meeting environmental targets without jeopardizing the trading market the program intends to create. The paper discusses the genesis of the two-tier credit system ACE helped to design, explains the differences between primary (fixed) and secondary (variable) credits, and outlines how the Dutch system is expected to function once implemented in 2004. The paper also discusses the market trading simulation held in early 2001 to assess and test the trading program, and reviews also the current status of the market program development. (+info)
A structural model that explains the effects of hyperglycemia on collagenolysis.
(6/98)
Prior investigations into the effects hyperglycemia on collagen degradation have yielded conflicting results. We present a new formalism for understanding the biochemistry of collagenolysis and the effects of hyperglycemia on collagen degradation. The analysis is based on an understanding of environments that affect the conformational stability of collagen. We suggest that collagen can exist in two distinct conformational states-a native state and a vulnerable state. Vulnerable collagen corresponds to a non-native conformation where partially unfolded regions near collagenase cleavage sites enable collagenases to efficiently degrade collagen. Theoretical calculations on collagen-like model peptides suggest that relatively short periods of hyperglycemia can alter the equilibrium distribution of states to favor vulnerable states of collagen. These data provide new insights into the mechanism of collagenolysis and resolve apparently discrepant experimental data on the effects of hyperglycemia on collagen degradation. (+info)
Powering the future: how Hamilton Health Sciences put cogeneration to work for healthcare.
(7/98)
The absolute necessity of a stable and uninterrupted power supply within hospitals makes many of these facilities uniquely suited to cogeneration plants. Hamilton Health Sciences recently completed the largest hospital cogeneration project ever undertaken in the country. Spanning three acute care hospitals and generating a combined total of 22.75 megawatts of electricity, Hamilton Health Sciences' cogeneration plants address energy supply issues by offering a clean and reliable power source completely within the hospital's control, and provide the organization with the potential to generate its own revenue into the future by selling excess electricity back to the province. The following article highlights Hamilton Health Sciences' approach to the project, including some important lessons learned, and may serve as an example for other publicly funded institutions interested in implementing similar projects. (+info)
Health, environmental, and economic costs from the use of a stabilized diesel/ethanol mixture in the city of Sao Paulo, Brazil.
(8/98)
In Greater Metropolitan Sao Paulo, Brazil, fossil fuel combustion in the transportation system is a major cause of outdoor air pollution. Air quality improvement requires additional policies and technological upgrades in fuels and vehicle engines. The current study thus simulated the environmental and social impacts resulting from the use of a stabilized diesel/ethanol mixture in the bus and truck fleet in Greater Metropolitan Sao Paulo. The evaluation showed reductions in air pollutants, mainly PM10, which would help avert a number of disease events and deaths, as estimated through dose-response functions of epidemiological studies on respiratory and cardiovascular diseases. Valuation of the impacts using an environmental cost-benefit analysis considered operational installation, job generation, potential carbon credits, and health costs, with an overall positive balance of US$ 2.851 million. Adding the estimated qualitative benefits to the quantitative ones, the project's benefits far outweigh the measured costs. Greater Metropolitan Sao Paulo would benefit from any form of biodiesel use, producing environmental, health and socioeconomic gains, the three pillars of sustainability. (+info)