Room-by-Room Energy Saving Tips:
Living/Family Room: Keep draperies and shades on south facing windows, which receive the most sunlight, open during the day to allow the sunlight to enter your home and closed at night to reduce the chill.
Newer homes more energy efficient than older ones
By Andrew Maykuth, Inquirer Staff Writer
Posted: March 09, 2013
The benefits of energy efficiency are hitting home.
Homes built in the last decade, despite being 30 percent larger than older dwellings, consume only 2 percent more energy on average, according to the U.S. Energy Information Administration.
The typical home built after 1999 consumed 21 percent less energy for space heating than older homes, according to EIA’s most recent Residential Energy Consumption Survey.
Improvements in the efficiency of heating equipment and better-insulated building shells accounted for much of the reduction, said James “Chip” Berry, manager of the residential survey, outlined Thursday in an EIA online newsletter.
Geography also had a role. More than half the newer homes were built in more temperate Southern states, where residents typically consume less energy heating.
The numbers affirm a long-term energy efficiency trend documented by the Energy Department. For the first time in decades, less than half of household energy use is now devoted to heating and cooling.
“The general trend over time has been that a decreasing share of household energy is used for heating and cooling,” said Berry, whose detailed survey is compiled every four years.
Heating and cooling declined as a share of household energy consumption from 58 percent in 1993 to 48 percent in 2009. Energy consumed on appliances, lighting and electronics – all those flat-screen TVs – has increased from 24 percent to 34 percent.
Households devote about 18 percent of their energy to water heating. That portion has remained steady in the last 20 years.
The EIA’s numbers are national averages. There are significant regional differences in energy consumption – residents in Northeastern states consume about 47 percent more on average than a household in the West.
The average U.S. household spent $2,024 on domestic energy expenses in 2009. The numbers were highest in cold states: Residents in the Northeast spent $2,595 a year, $1,027 more than residents in Western states.
New Jersey households, which tend to occupy more space than average, consume more energy (127.4 million Btus) than any state other than Illinois.
New Jersey households also consume the most energy among the 16 largest states, whose numbers were broken out separately: $3,065.
The shift in how energy is consumed in homes has occurred even as per-household energy consumption has steadily declined. But electricity has grown as a share of the total household pie.
Electricity and natural gas now account for equal amounts of the energy consumed on site in U.S. households. But it takes nearly three units of energy from primary fuels such as coal, natural gas, and nuclear fuel to generate one unit of electricity, so increased electricity use has a disproportionate impact on the amount of total energy consumed.
The typical U.S. household consumed 11,320 kilowatt hours of electricity in 2009, about two-thirds of which was used for appliances, electronics, and lighting.
Contact Andrew Maykuth at 215-854-2947, @Maykuth or amaykuth@phillynews.com.
Americans invest over 75% of their utility dollars on heating, cooling, lighting, cooking and running other appliances in their homes.
Americans invest over 75% of their utility dollars on heating, cooling, lighting, cooking and running other appliances in their homes. In fact, heating the shower water for a family of four can cost as much as $33 a month. Another reason to become more energy efficient. To learn more go to: http://www.energysavers.gov/tips/
Thanks to all who came to URE Energy Day!
Union Rural Electric Cooperative held its first ever Energy Day on Saturday, March 17th. Attending members heard “No Cost/Low Cost Energy Efficiency Tips” and “The Home Energy Audit” presentations from Paul Gillespie, URE energy advisor. These sessions provided members with easy and economical methods to help them lower their electric usage.
As a special bonus, Gina Zirkle from the Scotts Miracle-Gro environmental stewardship group presented Backyard Conservation: Lawns and the Environment. In addition, on hand was Possitivity for e-waste recycling and ShredDirect for secure on-site document shredding.
“Having an Energy Day gave us the opportunity to design a program geared towards assisting our members with energy saving tips,” commented Roger Yoder, URE president/CEO.
Union Rural Electric Cooperative, based in Marysville, Ohio, is a not-for-profit electric distribution cooperative serving more than 7,000 electric and 750 natural gas members. URE is a Touchstone Energy® Partner. For more information about URE, visit www.ure.com.
Marvell chip makes appliances and LED lights smart
Marvell Semiconductor is trying to get in on the ground floor of the smart home.
Today at the Consumer Electronics Show, the company announced a chipset that can add wireless networking to home appliances and LED light fixtures. The gear is designed to make it relatively cheap for manufacturers to make connected versions of common goods, such as thermostats and dishwashers.
A smart home that lets people remotely monitor and control appliances and electronics is likely to be a theme at CES this year as it was last year.
(Credit: Marvell)One of the technical challenges with making household items network-aware is that they typically don’t have very much computing power. Marvell’s Smart Appliances Platform includes a Wi-Fi wireless networking chip as well as a microcontroller to handle the processing involved in communicating with other devices, such as a smart meter or home control application.
The package also includes software that makes it relatively straightforward to write connected-appliance applications that can run on iOS or Android, said Kishore Manghnani, vice president of the green technology products group at Marvell. A dishwasher manufacturer, for example, could write an application so that a technician could remotely diagnose problems, or to allow a consumer to remotely control it.
Marvell has one appliance manufacturer that is planning on releasing a smart appliance based on the system in the second half of this year. With an added cost of $5, the net increase cost of a connected appliance to consumers is about $10, according to the company.
Marvell has created a similar platform aimed at lighting fixture and controller manufacturers. It’s first targeting commercial lighting and then hopes to address the consumer market.
The system uses Zigbee wireless chips, which would be embedded into a light fixture’s controller, and a small gateway device, which can communicate with 200 individual fixtures or bulbs.
At CES, Marvell plans to demonstrate how the wireless networking can allow a person to manage and schedule lighting from a central point to improve efficiency.
A number of companies, including Daintree Networks and Enlighted, are making wireless lighting systems intended to lower energy consumption. Marvell’s system will add a few dollars of cost to lighting fixtures, which will help drive smart lighting adoption, Manghnani said.
Making Energy Investment Decisions: The Time Value of Money
Key Points
- The principle that the value of money changes over time is important in making investment choices.
- Net present value and internal rate of return are financial analysis tools that account for the time value of money.
- The right tool to use depends on the type of financing, and the scope and nature of the project.
When considering energy efficiency investments, how do you decide whether a project is financially sound? Simple payback is a widely used method that answers the simple question “when do I get my money back?” Payback however, treats money only in its present day value, ignoring the fact that money changes value over time. Net present value (NPV) and internal rate of return (IRR) are financial analysis tools that account for the time value of money and may provide a more accurate view of the future costs and benefits associated with an energy project.
Net Present Value
NPV measures the financial worth of an energy project over time. It is the difference between the initial cost of the energy project and the present value of the annual savings or cash flows that result from it.
Unlike payback, cash values in NPV are adjusted or discounted so that near-term cash flows have a greater value than those in the more distant future. The discount rate is an interest rate used to adjust future cash flows to present value. The discount factor (DF) is the discount rate compounded annually and is used to calculate the present value based on the number of years. The choice of a discount rate can have a significant impact on an NPV calculation. The interest rate associated with the investment is often used. For example, if an energy project requires financing at 7%, then that could be used as the discount rate.
So, how can you use NPV to help make investment decisions? Let us use a lighting upgrade from T12 fluorescent lamps to more efficient T8 models as an example. You calculate that an initial investment of $12,000 will provide $16,000 in energy savings over four years. As the graphic below shows, the upgrade provides a simple payback in three years and a positive cash flow of $4,000. Using a discount rate of 7% however, the present value of the energy savings is reduced to $13,520, yielding an NPV of $1,520. While the cash flow is still positive, the calculation shows how the changing value of money can influence investments.
Internal Rate of Return
Internal rate of return (IRR) is closely related to NPV. IRR is a percentage figure that estimates the return on an energy-efficiency investment over time. In contrast to calculating NPV (where the discount rate is selected) an IRR calculation starts with the cash flow streams and finds the discount rate where the net present cash outflows and inflows breakeven—in other words, the NPV equals zero. Determining the IRR of an upgrade involves a tedious process of testing different discount rates until finding one where NPV equals zero. Fortunately, the task can be automated using a spreadsheet program or a financial calculator.
In the following calculation—using the lighting upgrade highlighted above—a discount rate of 12.6% would create an NPV of zero in four years. In a choice between multiple investment options, the one with the higher IRR is the better option. When the IRR is higher than the cost of financing, an energy-efficiency project is a financially sound investment.
Internal rate of return is easier to understand the NPV and provides a comparison to the cost of borrowing or the benefits of other investment options. However, IRR calculations are restricted to the initial capital investment and cannot take into account any subsequent financing. Also, IRR is a percentage figure that may provide a limited view of a project’s potential impact on profits.
Which Is the Better Option?
This is a difficult question to answer. The right tool to use depends on the type of financing, and the scope and nature of the project. NPV is useful for comparing projects with a fixed amount of years where multiple cash infusions may be required. It also provides a view of the financial benefits over the entire life of the project. IRR can compare projects with savings that occur over varying time periods. Also, since every investment involves risk, IRR can help compare financial options by establishing a hurdle rate, or the minimum amount of return required on an investment.
Whichever analysis tool you use, understanding the time value of money provides you with the ability to make better financial decisions.
“This article previously appeared in the Union Rural Electric Cooperative newsletter, and is used with permission.”
Useless grass could become the next biofuel
David Perlman, Chronicle Science Editor
Wednesday, October 12, 2011
BERKELEY –
One day in the not-too-distant future, we might be filling our cars with fuel made from useless grass.
A Berkeley biologist has transferred a gene from a variety of corn into a widespread, fast-growing species of the grass, and transformed it into what could become an important source of biofuel.
In a world of vanishing oil reserves, farmers have been growing more and more high-energy crops like corn and sugar cane to make ethanol as a replacement for gasoline, while scientists are seeking even higher-energy products from other and better crops.
Now George S. Chuck, a UC Berkeley plant geneticist, reports that his experiments with a species of corn called corngrass1 have yielded genetically altered forms of common switchgrass plants that more than doubles their content of starch.
The starch, in turn, creates sugars that when fermented – as in all biofuel plants – produce the ethanol that goes into more and more cars today.
Chuck and his colleagues are working at the Agriculture Department’s Plant Gene Expression Center in Albany.
In a report published this week in the Proceedings of the National Academy of Sciences, the scientists say that test plots of the altered switchgrass have shown that the gene experiments have improved the starch yield in the plants by “up to 225 percent.” Also important, they report, the gene transfer blocks the switchgrass plants from flowering.
“They’re forever young,” Chuck said – and that means the plants cannot spread pollen containing the new gene beyond the area where the altered plants grow.
Up to now, the fast-growing switchgrass, because of its tough lignin, an organic polymer, has required heavy chemical treatment before it can be turned to ethanol as biofuel. Chuck’s gene transfer experiments have shown that because the improved switchgrass keeps the plants young, the lignin content of their cells is minimal and would need no chemical treatment, he reported.
Edward M. “(Eddy)” Rubin, an internationally noted geneticist and director of the Department of Energy’s Joint Genome Institute in Walnut Creek, called Chuck’s report “both interesting and important.”
“This is an illustration of how manipulating the genome of a plant can make an incredibly useful change in the plant as a source of energy,” Rubin said.
Chuck’s gene-cloning experiments represent five years of work, Chuck said in an interview Tuesday.
Now, larger field tests of the transformed switchgrass are planned, and Chuck said he is starting a new series of genetics experiments to see how other genes from the corngrass1 plant can be “turned on” in response to light and darkness, and to raise the starch content of switchgrass even higher. The goal is a major new source of biofuel from a wild plant that grows throughout the world.
But drivers will have to be patient.
“It won’t all happen tomorrow,” he said.
E-mail David Perlman at dperlman@sfchronicle.com.
Happening this month: The 2011 Solar Decathlon
Students are once again vying to design and build the most cost-effective, energy-efficient and prettiest solar-powered home.
Two must-sees in Washington, DC this fall: one, the newly unveiled (though not officially dedicated due to hurricane upset) monument to Dr. Martin Luther King, Jr., designed by Chinese sculptor Master Lei Yixin. The other, the U.S. Department of Energy’s Solar Decathlon installation on the National Mall, from September 23-October 2, 2011.
The Decathlon is an award-winning collaborative program that engages teams from colleges across the world to design, build, and operate solar-powered houses that are cost-effective, energy-efficient, and pretty. The winner is the team that does it best, mindfully creating according to affordability, consumer appeal, and design excellence. It’s a free biennial event totally open to the public, who get to tour homes fathomed in nearby Maryland and as far imagined as New Zealand.
The purpose of the event is to educate student participants and the public at large about using clean-energy, the cost-effectiveness of energy-efficient construction and appliances, and providing students with training for the clean-energy workforce. Since 2002, the first year of the event, 72 houses have competed. Those houses are now dotted throughout the United States and the world serving educational, conservation, and community-oriented functions.
This year, nineteen teams are competing from the United States, Belgium, Canada, China and New Zealand. Here are a few we’re keeping our eye on.
From Middlebury College, “Self-Reliance.” A two-bedroom, 990-ft2 house designed for a family of four.
“First Light,” from Victoria University of Wellington, inspired by the traditional New Zealand holiday home—the “Kiwi bach.”
From the University of Maryland “WaterShed” proposes solutions to water and energy shortages.
CHIP from SCI-Arc is a design motivated by California’s “soaring land costs and urban sprawl.” It’s meant to be a minimal-footprint, affordable dwelling that offers a solution to the challenges of home ownership.
Out of Belgium, Ghent University’s E-Cube aims for simplicity stripped of nonessential components and finishes.
Visit Solar Decathlon for a full list of the participating teams, and tell us…what’s your favorite?
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Central Air Conditioners Why they don’t always live up to expectations.
Ever wonder why some rooms of your home may not be as comfortable as others in the summer? In most cases the culprits are the room return air ductwork. Even if you are exhausting cool air into the room you have to also be extracting the warmer, non-conditioned air. This means that the most important factor for central air conditioning is the return air location and size. Central air conditioning is all about removing heat from a room, period. That is, if the central air has been sized appropriately when spec’d for the home. All home air conditioning systems should be sized based on the Manual J Residential Load Calculation- 8TH edition version two, which is a part of the required CABO Code of Ohio.
A central air system that is sized correctly for cooling the house has to have the ductwork (exhaust and return) sized correctly to each room for the house to have uniform temperatures in each room. To better understand the significance of return air, we will assume the central air is sized correctly for the home in the following example. A two-story home with a central return air in the hallway on the second floor – 30” x 6” grille, will extract about 8,000 to 9,000 BTUS (¾ of a ton.) This may not be enough heat extraction to satisfy the second floor. The first floor may have two or three 30” x 6” return air grilles – causing the heat extraction to be three times greater on the first floor compared to the second floor. The thermostat located on the first floor would be temperature-satisfied significantly sooner than the second floor and would shut off the A.C. system. The second floor continues to build up heat including the heat that was not extracted in the first place. On a real hot day the second floor will never be close to being as cool as the first floor. The second floor should have more return air ductwork than the first floor. Additionally, the attic space builds up more heat than the outdoor temperature so the heat gain on the second floor will be greater. The first floor only has to contend with the heat gain from perimeter walls and windows whereas the second floor has that heat gain as well as from the ceiling. In most cases, a two-story home has more heat concerns than a one-story. However, even a single-floor home can have the same type of concerns.
The central air returns in a ranch home can cause the same type of concerns depending on the bedroom locations, living room and kitchen arrangement. Each area has a certain amount of heat gain without access to the return air- a closed bedroom door blocking the air flow to the return air grill limits the proper amount of heat extraction and causes the room to heat up. Other factors can cause central air to not cool properly – dirty air filters, the indoor air handler coil can become dirty and return air ductwork can be blocked with grime. Keep the grilles clear of furniture and draperies and realize size and location will make all the difference in heat removal of a particular area of a home or business.
