A recent study shows that shade trees on the west and south sides of a house in California can reduce a homeowner's summertime electric bill by about $25.00 a year. The study, conducted last year on 460 single-family homes in Sacramento, is the first large-scale study to use utility billing data to show that trees can reduce energy consumption.
"Everyone knows that shade trees cool a house. No one is going to get a Nobel Prize for that conclusion," says the study co-author, Geoffrey Donovan. "But this study gets at the details: Where should a tree be placed to get the most benefits? And how exactly do shade trees impact our carbon footprint?"
Donovan, a research forester with the Forest Service's Pacific Northwest (PNW) Research Station, is a co-author of the report with economist David Butry of the National Institutes of Standards and Technology. The report, "The Value of Shade: Estimating the Effect of Urban Trees on Summertime Electricity Use," has been submitted for publication to the journal Energy and Buildings.
The researchers chose to do their study on homes in Sacramento because of the city's hot summers and the fact that most people use air conditioners. The Sacramento Municipal Utility District operates an active tree planting program and residents are eligible for up to 10 free trees annually through a program delivered in partnership with the Sacramento Tree Foundation.
Some of the study's key findings are:
Placement of a tree is the key to energy savings. Shade trees do affect summertime electricity use, but the amount of the savings depends on the location of the tree.
Trees planted within 40 feet of the south side or within 60 feet of the west side of the house will generate about the same amount of energy savings. This is because of the way shadows fall at different times of the day.
Tree cover on the east side of a house has no effect on electricity use.
A tree planted on the west side of a house can reduce net carbon emissions from summertime electricity use by 30 percent over a 100-year period.
In 2007, the Sacramento Municipal Utility District gave its customers about 16,000 free trees (at a cost of $85.00 a tree). The district will recoup this investment in 26 years provided trees are planted on the west side of a house.
"Because homeowners experience virtually none of the carbon benefits of tree planting," says Donovan, "a subsidy to encourage tree planting seems warranted. Indeed, many of the benefits of urban trees have been shown to spill over to others in the community."
Sherri Richardson Dodge | EurekAlert!
Reusable carbon nanotubes could be the water filter of the future, says RIT study
30.03.2017 | Rochester Institute of Technology
Pan-European study on “Smart Engineering”
30.03.2017 | IPH - Institut für Integrierte Produktion Hannover gGmbH
The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.
To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
30.03.2017 | Health and Medicine
30.03.2017 | Health and Medicine
30.03.2017 | Medical Engineering