Determination analysis of energy conservation standards for distribution transformers

Abstract

This report has been reproduced directly from the best availaMe copy. This report contains information to assist the U.S. Department of Energy in making a determination on the feasibility and significance of energy conservation for distribution transformers as required by par. (a)( 1) above. The potential energy savings presented in this document are preliminary estimates appropriate for a determination study. Subsequent studies on this topic will involve more exact, detailed analysis on the effects of energy conservation standards for distribution transfonners. LIST OF TABLES ABSTRACTThe report contains information for the US. Department of Energy to use in making a determination on proposing energy conservation standards for distribution transformers as required by the Energy Policy Act of 1992. The potential for saving energy with more efficient liquid-immersed and dry-type distribution transformers could be significant because these transformers account for an estimated 140 billion kwh of the annual energy lost in the delivery of electricity. The objective of this study was to determine whether energy conservation standards for distribution transformers would have the potential for significant energy savings, be technically feasible, and be economically justified from a national perspective. It was found that energy conservation for distribution transformers would be technically and economically feasible. Sect. 6317) requiring that the U.S. Department of Energy (DOE) assess the feasibility of energy conservation standards for distribution transformers. The objective of this study was to determine whether energy conservation standards for distribution transformers would have the potential for significant energy savings, be technically feasible, and be economically justified from a national perspective. distribution system. Electrical energy is delivered to consumers by utility power transmission and distribution systems. The transmission network delivers power at high voltages (69-765 kV) from power plants to local distribution systems. Transmission voltages are used to transmit high levels of power over long distances. The high-transmission voltages require lower currents, which reduce line losses, conductor material, and costs. Once the electrical power has reached the distribution system, it is transformed to lower primary distribution voltages (ranging from 4 to 35 kV) that are more economical for the short distances within distribution systems. The primary distribution voltage is transformed by distribution transformers to lower secondary voltages (120-600 Vac) that are suitable for customer equipment. These transformers provide the final link in the chain of electrical power components from the generating sources to the ultimate power-consuming equipment.Distribution transformers are very reliable devices with no moving parts and average lives of -30 years. There are two basic types: liquid-immersed and dry-type. Liquid-immersed transformers typically use oil as a combination coolant and dielectric med...

The evaluation of a 4000-home geothermal heat pump retrofit at Fort Polk, Louisiana: Final Report

“…The lower power consumption after retrofit reduces the load on the transformers, thereby reducing their losses. Since this savings is not measured in building-level data, it is expected that savings measured at the feeder level will be somewhat higher (Barnes et al 1996). …”

Supplement to the ``determination analysis`` (ORNL-6847) and analysis of the NEMA efficiency standard for distribution transformers

“…In the absence of a definitive source for this breakout, it has been based on information from discussions with and informd information provided by transformer manufacturers. The loss characteristics describing utility transformers are probably more reliable than those for nonutilities because of the additional information from utility surveys (Barnes et al 1996).…”

“…4.3.3. Sources: Barnes et al 1994Barnes et al ,1996; NEMA letters to P. R. Barnes, September 15, 1995, andOctober 28, 1996; EEI utility survey (see Barnes 1994, Appendix A); and ORNLMEMA surveys of manufacturers in…”

“…The market for single-phase 10-kVA dry-type transformers is small, not significantly different from that for 15-kVA transformers, shown in million single-phase dry-type transformers of less than 10 kVA are currently sold in the market (with an average size of 1 kVA); these are used by original equipment manufacturers in machine tool applications. Distribution transformer applications in this size category usually average 3-to 5-kVA in capacity and currently have a share of -400,000 units (equivalent to 1200 MVA) of the total market of 1.4 million units (Barnes et al 1996). Therefore, the fact that single-phase dry-type transformers smaller than 15 kVA are not considered in the present study underestimates the total market for dry-type distribution transformers by 5.5% (in terms of megavolt-amperage).…”

“…This study -documented in the report Determination Analysis of Energy Conservation Standards for Distribution Transformers (Barnes et al 1996) -found that cost-effective, technically feasible energy savings could be achieved by distribution transformer standards and that these savings are significant relative to other product conservation standards. The final report was reviewed by a special transformer review group consisting of manufacturers, utilities, commercial and industrial users, research laboratories, contractors, materials suppliers, and public interest groups.…”