Free Newsletters - Space - Defense - Environment - Energy - Solar - Nuclear
..
. Energy News .




ENERGY TECH
Researchers find that some 'green' hot water systems fail to deliver on promises
by Staff Writers
Blacksburg VA (SPX) May 03, 2013


Randi Brazeau, left, and Marc Edwards, both of Virginia Tech, calculated that a typical consumer with an electric water heater would pay as much as $158 more annually compared to systems without recirculation. Credit: Virginia Tech.

Two researchers affiliated with the Virginia Tech College of Engineering have published a paper which reports that hot water recirculating systems touted as "green," actually use both more energy and water than their standard counterparts.

Marc Edwards, the Charles P. Lunsford Professor of Civil and Environmental Engineering in the Virginia Tech College of Engineering, originated the efficiency study of the systems as part of an undergraduate design class six years ago.

After a thorough analysis, the class concluded the claims as false, and that it "was thermodynamically impossible for these systems to save energy as claimed," said Edwards.

The topic was selected as part of a dissertation by Randi Brazeau during her doctorate in Virginia Tech's Charles E. Via Jr. Department of Civil and Environmental Engineering. The results are presented in a paper published in the most recent issue of Journal of Green Building.

Brazeau, now an assistant professor of environmental science at Metropolitan State University of Denver, examined the energy and water savings of continuous hot water recirculating systems in a comparative, direct test versus traditional hot water systems in which consumers often wait for the cold water to flush down the drain before the water warms to a comfortable temperature for showering.

She found that the recirculation systems used 20 percent more energy even in the best possible scenario in which the water pump was only on for a few seconds before use, and in scenarios where the pump was always on, the recirculation systems could require more than double the energy to operate. The consumer pays for this extra energy in higher electric and fuel bills.

"Randi demonstrated that when all energy costs are accounted for, including that necessary to run the pump, the hot water recirculating systems always used much more energy than the conventional systems," said Edwards.

A previous U.S. Department of Energy report and certain manufacturers claimed the recirculation devices would not only eliminate wait times, but also would save both water and energy.

It also was assumed that because consumers did not need to wait for water to warm, the hot water recirculation systems would at minimum save water from being wasted. But that claim did not consider that it takes water to make energy, said Edwards.

The research found that the "so-called green" hot water recirculation systems used more net water than the conventional systems after accounting for water needed to produce the extra energy.

"These are really consumer comfort and convenience devices, a luxury really, masquerading as 'green' or environmentally conscious devices," Edwards said.

Other findings: On-demand electric systems operate with nearly 100 percent energy efficiency, but cannot be used in many circumstances dependent on scaling and incoming water temperature, and may require expensive upgrades to home electrical systems and use of low or ultra-low flow showerheads.

In many cases, hot water recirculating systems touted as "green" are not just a consumer choice, but required in some new homes and businesses in the United States, said Brazeau. But their energy savings, and therefore lessened environmental impact claimed by manufacturers "do not hold water," she added.

Brazeau and Edwards calculated that a typical consumer with an electric water heater would pay as much as $158 more annually compared to systems without recirculation. More research, though, is necessary to better inform policy and decision-making by regulators, public health officials, manufacturers, and consumers, Edwards and Brazeau said.

.


Related Links
Virginia Tech
Powering The World in the 21st Century at Energy-Daily.com






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News





ENERGY TECH
Saint-Gobain Announces Strategic Initiatives in Renewable Energy
Willich, Germany (SPX) May 02, 2013
An early glimpse into the 2013 Annual Energy Outlook from the US Energy Information Administration reveals that increased generation from renewable energy is expected to account for 32 per cent of the overall domestic growth in electricity generation from 2011 to 2040. With this insight and reports of global growth forecasts in renewable energy from both financial and market analysts in mind, Sa ... read more


ENERGY TECH
Environmental Labels May Discourage Conservatives from Buying Energy-Efficient Products

Ethiopia and China sign $1 billion power deal

New York approves power line from Canada

$674 billion annual spend on 'unburnable' fossil fuel assets signals failure to recognise huge financial risks

ENERGY TECH
Potential of best practice to reduce impacts from oil and gas projects in the Amazon

Researchers find that some 'green' hot water systems fail to deliver on promises

Wales tidal energy energy project nabs $2.9 million in EU funding

East Africa's 'embarrassment of riches' in energy

ENERGY TECH
Scotland approves 640-foot prototype offshore wind turbine

Wind Power: TUV Rheinland Certifies HybridDrive from Winergy

Wales wind power line to go underground near historic village

UK Ministry of Defense Deems Wind Towers a National Security Threat

ENERGY TECH
Community Solar Coming to City of Aurora and Arapahoe County

Thin-film technology fuels ITN Energy Systems

JA Solar and Flextronics Enjoy Booming Solar Module Growth

Trina Solar presents new high-efficiency products and focus on extended service proposition

ENERGY TECH
Japan, Turkey sign $22-bn nuclear deal

Japan signs nuclear cooperation deal with UAE

Japanese-French led group to build Turkish nuclear plant

Texas A and M Physicist Sees Energy Solutions in Green Nuclear Power Technology

ENERGY TECH
Recipe for Low-Cost, Biomass-Derived Catalyst for Hydrogen Production

China conducts its first successful bio-fueled airline flight

Bugs produce diesel on demand

New input system for biogas systems

ENERGY TECH
On Course for Shenzhou 10

Yuanwang III, VI depart for space-tracking missions

Shenzhou's Shadow Crew

Shenzhou 10 sent to launch site

ENERGY TECH
The politics of climate change

China becoming global climate change leader: study

China a leader in fight on climate change?

Ireland: EU consensus exists for setting 2030 greenhouse gas targets




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement