News Room : Archives : June 2011

 

Posts Tagged ‘water-per’

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Best Energy Efficient Dishwashers 2011

Sunday, June 26th, 2011

Looking at reviews to find the best, energy efficient dishwasher for your home? Good idea!

Your home appliances can really add to your energy bills — and your carbon footprint.

If you’re in the market for a new dishwasher, look for a model that’s Energy Star certified. Energy Star is a program that was started by the U.S. Environmental Protection Agency in the 1990′s. It created a certification standard for energy-efficient computers and appliances. The EPA says that in 2006, $14 billion were saved in energy costs through the implementation of Energy Star products.

Most energy-efficient dishwashers

Bosch Model SHE68E05UC

Here’s a list of the top ten best dishwashers available in the U.S. in 2011, ranked strictly by efficiency. Most of these are premium dishwashers, so you’ll also get a quiet dishwasher that cleans well too. Model numbers with asterisks (*), contain characters that denote color, or another variable unrelated to energy efficiency. This list was compiled using Energy Star’s Energy Factor criteria, which is a measurement of energy use per cycle. The higher the Energy Factor, the better.

When shopping for dishwashers, Energy Star recommends buying one with an appropriate size. Dishwashers that are run full are the most energy-efficient. Standard-size models tend to hold 8 or more place settings, while compact (drawer) models hold 7 or less. Get a compact model if you only generate a few dishes on a daily basis. Also, dishwashers with multiple wash-cycle options (for lightly-soiled dishes, for example), can help you save additional energy.

10. Asko D5893XXL** dishwasher

This Swedish Asko extra-large model can hold up to 17 place settings and runs quietly at 45 decibels. It features 12 wash programs and 9 temperature settings. Asko claims that their 500-series models have more usable height than any other dishwasher. It retails for $1,750. Energy Star says it will use 187 kwh of electricity a year, 3.8 gallons of water per cycle, and its Energy Factor rating is 1.16.

9. Bosch SHX68E05UC dishwasher

Bosch makes the most energy-efficient standard-size dishwashers, as rated by Energy Star. They also offer multiple washing options, load sensors and adjustable racking, among many other options that all contribute to high performance and retail price. This model holds 15 place settings and retails at $1,800. It uses an estimated 180 kwh a year and an average of 1.56 gallons of water per cycle. Its Energy Factor rating is 1.19.

8. Bosch SHE68E15UC dishwasher

A standard-sized model with a laundry-list of sweet features. Adjustable racks, six wash settings with five additional options per setting and superior drying and an ability to effectively sanitize dishes. It has the same Energy Star specifications and Energy Factor rating as the other Bosch dishwashers listed and retails at $2,100.

7. Bosch SHE68E05UC

This model is standard-sized and features adjustable racks and a toned-down version of our last entry. It’s super-quiet at 42 decibels. It’s Eco Sense and Eco Action settings can reduce the unit’s energy consumption by 20%. It has six wash settings, uses an average of 1.56 gallons of water and 180 kwh a year, with an Energy Factor rating of 1.19. It retails at $1,650.

6. Bosch SHV68E13UC dishwasher

This standard-sized model has a half-load feature, among its six cycle options. It runs at 40 decibels and lists a staggering array of further options. It has the same kwh and water usage options as the previous Bosch entries, as well as the same Energy Factor rating. It retails at $2,100.

5. Kenmore 1332 dishwasher

This is Kenmore’s drawer-style compact model. It comes with a food disposer and variable cleaning cycles. It will use about 174 kwh a year and uses an average of 2.7 gallons of water per cycle. Its Energy Factor rating is 1.3. It retails for $655.

4. KitchenAid KUDD03ST dishwasher

KitchenAid’s compact drawer model, the KUDD03ST features their Pro Dry system for drying your dishes and a sound insulation system for quiet cycles. It will use an estimated 174 kwh of electricity a year and 2.7 gallons of water per cycle. Energy Star gives it an Energy Factor of 1.3. It costs around $1,000.

3. Fisher & Paykel  DD24S** dishwasher

The older, slightly less-efficient model of Fisher & Paykel’s Dish Drawer model (see newer model below), it features a fully-adjustable racking system and load sensors to maximize performance, as well as some extra space, though it’s still compact. It uses an estimated 160 kwh anually, as well as 2.9 gallons of water per cycle. It has an Energy Factor rating of 1.39. It retails for around $630.

2. Fisher & Paykel DCS DD124 dishwasher

The commercial version of Fisher & Paykel’s most energy-efficient compact dishwasher. It has nine wash settings, and a 163-degree sanitizing setting. It holds 6 place settings and uses 157 kwh/year and 2.9 gallons of water per cycle. It has an Energy Factor Rating of 1.39 and retails for around $989.

1. Fisher & Paykel DD24S* V2 dishwasher

This is a compact model with a fully-adjustable rack system. It holds plates up to 13 inches. It uses 2.11 gallons of water per cycle and uses 154 kwh of power per year. Its Energy Factor rating is 1.43. It retails for around $630.

Do you own any of these dishwashers? If so, please leave a comment with your opinion about it, so that others who are doing research before they buy a dishwasher can get your feedback and choose well.

Go here to read the rest:
Best Energy Efficient Dishwashers 2011

Heat-Pump Water Heaters

Saturday, December 11th, 2010

Heat-Pump Water Heaters

Heat-pump water heaters produce more than twice as much hot water per kilowatt-hour (kWh) of electricity consumed as standard electric water heaters. How do they work and when do they make sense?

A heat pump relies on the well-understood refrigerant cycle to move heat from one place to another. The same basic principle used for a refrigerator can also be used to heat water. While an electric-resistance water heater (the standard electric storage water heater that is sold by the millions each year) converts electricity directly into heat, a heat pump water heater uses electricity to extract heat from the room and deliver it—at a higher temperature—into the water. In doing so, the “efficiency” jumps from somewhat less than 100% (for electric resistance water heating) to more than 200%.

Heat-pump water heaters can either be self-contained, with a heat-pump unit that’s directly integrated with the storage tank, or modular, with an add-on heat-pump unit that connects to a standard storage-type water heater. In either case, a fan pulls air from the room into a heat exchanger core where its heat is transferred to refrigerant in copper coils—this occurs in the evaporator coil. The refrigerant is colder than the circulating air, so heat is transferred to the refrigerant, evaporating it. A compressor mechanically compresses the refrigerant gas, raising its temperature. The warm refrigerant gas then passes through a condensing coil, where it is condensed by the (cooler) circulating water from the storage tank, heating the water in the process. The refrigerant liquid then passes through an expansion valve where the temperature drops and the cooler refrigerant enters the evaperator coil to repeat the cycle.

Energy performance of heat-pump water heaters is measured as either the coefficient of performance (COP) or Energy Factor. The COP, used for modular heat-pump water heaters, is a simple measure of instantaneous efficiency—a COP of 2.5 means an efficiency of 250%. Energy Factor is used for integral heat-pump water heaters, accounting for storage losses, and is a more accurate measure of actual performance.

Self-contained heat-pump water heaters are made by a number of companies, including Rheem, GE, and Stiebel-Eltron. Add-on heat pump units that attach to conventional storage-type water heaters are made by A.O. Smith, AirGenerate, and North Road Technologies.

A heat-pump water heater extracts heat from the space where it is installed—cooling the room—so this should be considered when determining placement. If it’s installed in conditioned space, your heating system is going to use more fuel, and that effectively reduces the energy performance of the heat-pump water heater. During summer, the cooling and dehumidification of room air is an advantage—providing free air conditioning.

Heat-pump water heaters have fans and pumps, which will generate some noise—similar to a refrigerator. Unlike standard water heaters, they also require condensate drains to remove moisture that condenses on the evaporator coil.

December 1, 2010

Original Post by BuildingGreen.com
Heat-Pump Water Heaters

DOE To Ban Multi-Spray Showerheads

Sunday, August 8th, 2010

DOE To Ban Multi-Spray Showerheads

The U.S. Department of Energy (DOE) has issued a draft interpretive ruling on the definition of “showerhead” as used in the Energy Policy and Conservation Act (EPCA). Sidestepping public comment procedures, DOE has defined “showerhead” in a way that makes multi-spray systems illegal. The new ruling states that all of the fixtures used in a multi-spray system must, combined, use no more than 2.5 gallons of water per minute.

EPCA, first passed in 1975 and updated several times since then, limits water use by showerheads to 2.5 gallons per minute (gpm; 9.5 lpm) at 80 psi. The law does not, however, specify what a “showerhead” includes, so manufacturers have been able to sell shower systems with multiple heads, each of which conforms to the 2.5 gpm limit. These multi-spray systems can include body sprayers and other fixtures, and sometimes use upwards of 20 gpm (76 lpm). Marketed as a high-end product, with high prices to match, these systems are not installed frequently.

DOE’s ruling came as a surprise to plumbing manufacturers and conservationists alike, since it lacked the public comment process required for substantive rule changes. But DOE considers the ruling an interpretation of an existing law, and thus “exempt from the notice and comment requirements of the Administrative Procedure Act,” in its wording.

A letter to DOE from a coalition of industry groups noted: ”A change of this magnitude should not be exempt from the notice and comment requirements of the Administrative Procedures Act as DOE has asserted.” It also argues that the ruling would affect hand-held showers and other fixtures “used in hospitals, nursing homes, schools, and other therapeutic and medical facilities.” Marsha Mazz, the Technical Assistance Coordinator for the U.S. Access Board, disagrees with the assertion that the ruling could adversely affect the showerheads used by the elderly and disabled. “We don’t see it as a disability issue at all,” she said.

Conservation-minded observers worry that the lack of a public comment period will allow manufacturers to find loopholes in the language of the ruling, leading to increased water use. “This is a substantive change and working out all the definitions and conditions to make sure the language is watertight will take a lot of effort from a lot of folks,” said water expert John Koeller, P.E.

– Peter Yost and Allyson Wendt

Read this article:
DOE To Ban Multi-Spray Showerheads

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