Tag Archives: energy
Heat
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Heat is energy transferred due to temperature differences only.
- Heat transfer can alter system states;
- Bodies don’t “contain” heat; heat is identified as it comes across system boundaries;
- The amount of heat needed to go from one state to another is path dependent;
- Adiabatic processes are ones in which no heat is transferred.
The overall heat loss from a building can be calculated as
H = Ht + Hv + Hi (1)
where
H = overall heat loss 
Ht = heat loss due to transmission through walls, windows, doors, floors and more
Hv = heat loss caused by ventilation
Hi = heat loss caused by infiltration
Insulation Thickness, Thermal Conductivity & Performance Criteria
Systems thinking
Systems thinking involves the use of various techniques to study systems of many kinds. In nature, examples of the objects of systems thinking include ecosystems – in which various elements (such as air, water, movement, plants, and animals) interact. In organizations, systems consist of people, structures, and processes that operate together to make an organization “healthy” or “unhealthy”. Systems Engineering is the discipline that utilizes systems thinking to design, build, operate and maintain complex engineered systems.
SCHOOLS OF THOUGHT
The Circular Economy concept has deep-rooted origins and cannot be traced back to one single date or author. The generic concept has been refined and developed by the following schools of thought:
• Regenerative design (representative: John T. Lyle).
• Performance economy (representative: Walter Stahel).
• Cradle to Cradle (representatives: Michael Braungart and William McDonough)
• Blue Economy (representative: Gunter Pauli)
• Permaculture (representatives: Bill Millison and David Holmgren)
• Biomimicry (representative: Janine Benyus)
• Industrial Ecology (this is more than a school of thought, it is an academic discipline that has been taught from the 1990s)
The evaluation of processes that protect the environment alongside resource and energy consumption to most favourable to least favourable actions.[1] The hierarchy establishes preferred program priorities based on sustainability.[1] To be sustainable, waste management cannot be solved only with technical end-of-pipe solutions and an integrated approach is necessary.[2]
The waste management hierarchy indicates an order of preference for action to reduce and manage waste, and is usually presented diagrammatically in the form of a pyramid.[3] The hierarchy captures the progression of a material or product through successive stages of waste management, and represents the latter part of the life-cycle for each product.[3]
The aim of the waste hierarchy is to extract the maximum practical benefits from products and to generate the minimum amount of waste. The proper application of the waste hierarchy can have several benefits. It can help prevent emissions of greenhouse gases, reduces pollutants, save energy, conserves resources, create jobs and stimulate the development of green technologies.[4]
All products and services have environmental impacts, from the extraction of raw materials for production to manufacture, distribution, use and disposal. Following the waste hierarchy will generally lead to the most resource-efficient and environmentally sound choice but in some cases refining decisions within the hierarchy or departing from it can lead to better environmental outcomes.[5]
Life cycle thinking and assessment can be used to support decision-making in the area of waste management and to identify the best environmental options. It can help policy makers understand the benefits and trade-offs they have to face when making decisions on waste management strategies. Life-cycle assessment provides an approach to ensure that the best outcome for the environment can be identified and put in place.[5] It involves looking at all stages of a product’s life to find where improvements can be made to reduce environmental impacts and improve the use or reuse of resources.[5] A key goal is to avoid actions that shift negative impacts from one stage to another. Life cycle thinking can be applied to the five stages of the waste management hierarchy.
For example, life-cycle analysis has shown that it is often better for the environment to replace an old washing machine, despite the waste generated, than to continue to use an older machine which is less energy-efficient. This is because a washing machine’s greatest environmental impact is during its use phase. Buying an energy-efficient machine and using low- temperature detergent reduce environmental impacts.[5]
The European Union Waste Framework Directive has introduced the concept of life-cycle thinking into waste policies.[5] This duality approach gives a broader view of all environmental aspects and ensures any action has an overall benefit compared to other options. The actions to deal with waste along the hierarchy should be compatible with other environmental initiatives.
Published on Apr 27, 2016
Dark energy, what exactly does it do? Find out in this episode of Space Time! Part 3 in our Dark Energy series.
Part 1: https://www.youtube.com/watch?v=xZTb6…
Part 2: https://www.youtube.com/watch?v=-4Pay…
Jevons paradox
In economics, the Jevons paradox (/ˈdʒɛvənz/; sometimes Jevons effect) occurs when technological progress increases the efficiency with which a resource is used (reducing the amount necessary for any one use), but the rate of consumption of that resource rises because of increasing demand.[1] The Jevons paradox is perhaps the most widely known paradox in ecological economics.[2] However, governments and environmentalists generally assume that efficiency gains will lower resource consumption and are an effective policy for sustainability, ignoring the possibility of the paradox arising.[3]
In 1865, the English economist William Stanley Jevons observed that technological improvements that increased the efficiency of coal-use led to the increased consumption of coal in a wide range of industries. He argued that, contrary to common intuition, technological progress could not be relied upon to reduce fuel consumption.[4]
The issue has been re-examined by modern economists studying consumption rebound effects from improved energy efficiency. In addition to reducing the amount needed for a given use, improved efficiency lowers the relative cost of using a resource, which tends to increase the quantity of the resource demanded, potentially counteracting any savings from increased efficiency. Additionally, increased efficiency accelerates economic growth, further increasing the demand for resources. The Jevons paradox occurs when the effect from increased demand predominates, causing resource use to increase.[4]
Considerable debate exists about the size of the rebound in energy efficiency and the relevance of Jevons paradox to energy conservation. Some dismiss the paradox, while others worry that it may be self-defeating to pursue sustainability by increasing energy efficiency. However, conservation policies such as green taxes, cap and trade, and emissions standards do not display the paradox, and can be used to control the rebound effect.[5] Environmental economists have proposed that efficiency gains be coupled with conservation policies that keep the cost of use the same (or higher) to avoid the Jevons paradox.[
Mass and energy
JPL to Assist in Oil and Gas Tech Development
Charles Elachi, director of NASA’s Jet Propulsion Laboratory in Pasadena, Calif., met with top executives of the Norwegian-based oil and gas company, Statoil, on Friday, Nov. 22, in a ceremonial signing of a new agreement to assist in the development and subsequent transfer of technologies to Statoil and America’s oil and gas activities. The focus will be on enabling safe and efficient development and production of U.S. and world fossil fuel reserves.
Technologies developed by JPL for the harsh and difficult environments of space will be applied to the demanding environments of oil and gas production. The agreement also provides an opportunity for JPL to benefit from synergistic technology currently being developed in the oil and gas sector that might be used for space exploration.
Statoil has large holdings in the U.S., in such challenging environments as offshore and tight shale formations. It is number 39 on the Forbes 500 list of the world’s largest companies.
“This agreement is the latest example of how NASA and JPL technologies can benefit us here on Earth. It’s also an example of how collaborations with other industries can be beneficial to space exploration,” said JPL Director Charles Elachi.
In addition to a general tour of JPL prior to the signing ceremony, Statoil representatives also had an opportunity to see JPL’s Microdevices Laboratory, where some of these technologies are being developed.
The California Institute of Technology in Pasadena manages JPL for NASA.
waves and tides in Scotland
Published on Dec 13, 2012
This short film, narrated by scientist and TV presenter Heather Reid at Whitelees Windfarm, explores the opportunities for using the power of the wind, waves and tides in Scotland to produce energy.
Heather speaks to Laura Watson, an engineer with Scottish Renewables, who explains how wind and tidal turbines works and the difficulties of using these turbines including selecting the best location and under-water maintenance.
Tom Wills, an engineer from Aquamarine, explains how his company’s new Oyster technology converts wave energy into power. Storms in the Scottish sea are just one of the challenges they face.
Video and all copyright belongs to: Education Scotland
Scotland has the ambitious goal of getting 100% of its electricity from renewables by 2020, and it is making amazing progress toward attaining it. Although many provinces or countries get 60% or more of their electricity from renewables, most of these depend mainly on hydro-electic. For those without riparian resources, the challenge is to implement other renewable energy generating technologies. Scotland is favorably situated to develop wind power, and is going for it in a big way.
Based on the performance of the first three quarters, Scotland was on track in 2012 to generate 15 percent more electricity from renewablesthan in the previous year (which also broke earlier records).
In 2011, Scotland was already getting 36 percent of its electricity from green energy, ahead of its target of 31 percent! In 2012 alone, renewables are estimated to have attracted $1 billion in investments. Pete Danko writes of these investments, which have produced 11,000 jobs at a time of economic retrenchment, “Maybe this is what happens if you have a national policy that encourages not just incremental but radical transitioning to renewable energy: Not only do you get clean energy, you get a lot of the manufacturing infrastructure that comes with it.”
In 2011, Scotland had generated 13.735 gigawatt hours from renewable sources (up 44.3% from 2010 and an increase of 97.3% from 2006). Unlike in Portugal, a relatively small portion– only about a gig — of that was from hydroelectric.
Scotland is planning the world’s largest offshore wind farm.
Some of the Scottish have even put in solar panels and use solar thermal to heat water. Although solar is a harder technology to profit from in overcast Scotland than wind, it can be part of the renewable mix there. The government is also now experimenting with wave energy, which could be huge for Scotland, as well as tidal energy.
The UK in general is now wavering on commitment to renewables, under the Tory government of David Cameron, and national policy may hobble Scotland’s efforts a bit. BP and other Big Carbon interests (and Donald Trump) are propagandizing against wind as ruining the beauty of the countryside, as though oil rigs do not, or as though catastrophic climate change would be better.
Quantitative Approaches to Environmental Sustainability in Transportation Networks
Call for papers
A special issue of Networks & Spatial Economics on “Quantitative Approaches to Environmental Sustainability in Transportation Networks”
Guest Editor: Dr. W.Y. Szeto
Department of Civil Engineering
The University of Hong Kong
Pokfulam
Hong Kong
Scope and topics
Environmental sustainability is closely related to transportation, especially the road network, because vehicle emissions and noise damage the environment and have adverse effects on human health. Some of vehicle emissions are even greenhouse gases that contribute to climate change. It is therefore important to quantify their effect and take their effect into account when designing, planning, managing and controlling transportation networks. Currently, environmental sustainability is a hot topic and many efforts have been put on developing quantitative approaches and transportation network models to address environmental sustainability issues related to transportation. This special issue focuses on the recent advances of quantitative approaches to environmental sustainability in transportation networks. Topics of interest include, but are not limited to, the following:
• bike network design
• bike sharing
• car sharing
• carbon footprint
• electric vehicles
• environmental impact assessment
• environmental-friendly parking fee
• Intelligent transportation systems
• road pricing with environmental externality
• tradable credit and emission pollution permits
• traffic assignment with environmental constraints
• transit network design
• transportation network design
• vehicle emissions
• vehicle noise
You are invited to submit a full paper to this special issue of Networks & Spatial Economics with Science Citation Index (SCI).
Submission method
The length of each paper, including the abstract and references, may not exceed 10,000 words (note that each table, figure, or photograph accompanying the text counts as 250 words). The paper should submit to the online system at
http://www.editorialmanager.com/nets/
and will go through a normal peer review process. During the submission, please choose the article type “S.I: Environmental Sustainability in Transportation Networks”, and place “Sustainability SI:” in the original title of the paper. These words will be removed prior to publication.
Selection criteria and paper format
All manuscripts of high quality will be accepted for publication. Criteria for acceptance include originality, contribution, scientific merit, accuracy and readability. The final paper format must follow the standards found in Networks and Spatial Economics:
http://www.springer.com/economics/regional+science/journal/11067
Submission of full paper due: October 15, 2012
Feedback from first-round reviews issued: February 15, 2013
Revised manuscripts due: April 15, 2013
Feedback from second-round reviews issued (if needed): June 15, 2012
Final manuscripts due: August 15, 2012
Planned publication: early 2014
Inquires
Inquires should be directed to
Dr. W.Y. Szeto
Email: ceszeto@hku.hk
Tel: (852) 28578552
conlatio 