Note however that almost half the residential energy (49%) is lost in transmission and distribution.
EIA estimates that national electricity transmission and distribution losses average about 6% of the electricity that is transmitted and distributed in the United States each year.
Surf wrote:Note however that almost half the residential energy (49%) is lost in transmission and distribution.
According to the EIA:EIA estimates that national electricity transmission and distribution losses average about 6% of the electricity that is transmitted and distributed in the United States each year.
Source:http://www.eia.gov/tools/faqs/faq.cfm?id=105&t=3
Primary energy consumption in the residential sector totaled 20.99 quadrillion Btu (quads) in 2009, equal to 54% of consumption in the buildings sector and 22% of total primary energy consumption in the U.S. Nearly half (49%) of this primary energy was lost during transmission and distribution (T&D). Energy consumption increased 24% from 1990 to 2009. However, because of projected improvements in building and appliance efficiency, the Energy Information Administration’s 2012 Annual Energy Outlook forecast a 13% increase from 2009 to 2035.(2.1.1)
Surf wrote:Government regulations have resulted in substantial saving in appliances such as refrigeration and lighting. all refrigerators in the stores today are more efficient than they were 15 years ago. In many places incandescent bulbs have been banned and are being phased out in favor of LED and CFL bulbs.
However as to homes, in many cases you need to do a major remodel to make the walls thicker for more insulation . Many remodels don't address efficiency at all. Also building codes in many places are old and have not been updated to require more insulation and many need homes are not tested for air leakage through the walls. As a result today's new homes are frequently not much more efficient than homes built 30 years ago. Government could pass a law requiring all new home be passive houses with PV and or solar thermal systems but many state and local governments arn't doing it. It has been done for cars but not for buildings.
Paulo1 wrote:Yeah Surf,
When I read KJ's stat I immediately thought he must have been talking about ultimate efficiency and not electrical transmission.
After all, that is the whole reason for step-up transformers and high voltage lines....lower the amperage and reduce losses. Otherwise, we would still be in a DC world with low voltage supplies.
I still think that ultimate savings are made in simple solutions such as passive solar and high insulation. Complex housing systems require too much upfront expenditures for what is ultimately gained. Furthermore, a healthy house requires aduquate air exchange.
paulo
According to the EIA:
EIA estimates that national electricity transmission and distribution losses average about 6% of the electricity that is transmitted and distributed in the United States each year.
Source:http://www.eia.gov/tools/faqs/faq.cfm?id=105&t=3
My information came from this DOE web page: http://buildingsdatabook.eren.doe.gov/C ... ntro2.aspx
Primary energy consumption in the residential sector totaled 20.99 quadrillion Btu (quads) in 2009, equal to 54% of consumption in the buildings sector and 22% of total primary energy consumption in the U.S. Nearly half (49%) of this primary energy was lost during transmission and distribution (T&D). Energy consumption increased 24% from 1990 to 2009. However, because of projected improvements in building and appliance efficiency, the Energy Information Administration’s 2012 Annual Energy Outlook forecast a 13% increase from 2009 to 2035.(2.1.1)
The 6% T&D figure is for the entire electric grid, and I agree with it. But residential electrical power includes both suburban and rural residences where pole-mounted or small buried transformers are used - and when it comes to transformers, efficiency comes with size. There are only a few transformer sizes, as well. I knew a farmer with a house and barn and three widely separated outbuildings - and FIVE small pole-mounted transformers and power meters.
In section 5 the efficiencies for transformers with a max load of 140 to 3000 watts. Minimum efficiency shown is 98.86%.
I therefore think the DOE website is in error, or they are referring to the losses in the home only. Many older wall wart transformers are just cheep transformers with an efficiency of 30 to 50%. Most new electronic now have switching AC to DC converters that are typically have an efficiency of 80 to 95%. In sum places high efficient AC to DC conveters are now required by law. If you factor old inefficient wall warts with with lighting losses and low efficiency fans in furnaces the DOE figure makes sense for just the home. I could be wrong but that is the way it looks to me.
If you really want to upgrade the transformers across the country you could have the IRS announce a tax credit for every old style unit replaced with a new style laminated core unit. That would lead to a rapid switch over from old to new as companies went for the tax credit incentive. Instead all we get are thousands of hours of politicians talking about smart meters that can shut off your personal appliances if they think it is a good idea.
DOE's analyses indicate that today's standards would save a significant amount of energy. The lifetime savings for equipment purchased in the 30-year period that begins in the year of compliance with amended standards (2016-2045) amounts to 3.63 quads.
The cumulative net present value (NPV) of total customer costs and savings of today's standards for distribution transformers, in 2011$, ranges from $3.4 billion (at a 7-percent discount rate) to $12.9 billion (at a 3-percent discount rate). This NPV expresses the estimated total value of future operating-cost savings minus the estimated increased equipment costs for equipment purchased in 2016-2045, discounted to 2012.
In addition, today's standards would have significant environmental benefits. The energy savings would result in cumulative emission reductions of 264.7 million metric tons (Mt) (5) of carbon dioxide (CO 2), 223.3.thousand tons of nitrogen oxides (NO X), 182.9 thousand tons of sulfur dioxide (SO 2), and 0.6 ton of mercury (Hg). (6)
The value of the CO 2 reductions is calculated using a range of values per metric ton of CO 2 (otherwise known as the Social Cost of Carbon, or SCC) developed by a recent interagency process. The derivation of the SCC values is discussed in section IV.M. DOE estimates the net present monetary value of the CO 2 emissions reduction is between $0.80 billion and $13.31 billion, expressed in 2011$ and discounted to 2012. DOE also estimates the net present monetary value of the NO X emissions reduction, expressed in 2011$ and discounted to 2012, is $93.2 million at a 7-percent discount rate and $234.1 million at a 3-percent discount rate. (7)
KaiserJeep wrote:
The answer is YES, we need to save every BTU we can, and NO, we need to constrain population to where it is today, and actually decrease it from the present extreme overshoot. Which we have kicked around in PO.com in endless variation, and nobody knows how to do.
Is something so different with the transformers used in the US that causes them to lose so much energy? The ones we have here, only get noticeably warm under high loads and normally produce very little heat.
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