also helped ASHRAE draft a voluntary standard for testing entire solar hot water heating systems.

When analyzing performance data on solar equipment to see whether or not it meets standards or how it compares with other companies' products, is it first necessary to know where the equipment tests were run or who performed the tests? In other words, does it matter whether the tests took place in Phoenix or Seattle, or whether they were administered by a nationallyknown testing laboratory or the equipment manufacturer?

Manufacturers, designers, and prospective purchasers of solar equipment need to know the answers to these questions. Helping in this task, NBS has been working in a DOEsponsored program to speed the establishment of an accredited network of solar testing laboratories. The Bureau completed several major projects to that end. For example, NBS organized a round robin test of solar collectors involving 21 laboratories across the

furnaces and boilers. The new laboratory will help the Bureau reach two related and important goals: improving current technology used to measure what actually happens in the harsh environment of utility and industrial combustors, and developing a way to predict what will occur inside these combustors.

There currently is a critical lack of information on the thermal effectiveness of high temperature industrial insulators, particularly refractory materials used in the walls of furnaces. Although many of these materials are exposed to and operate at temperatures above 500 °C, there are wide disparities in the thermal conductance values assigned to individual materials. If better information were available about the heat transmission of these insulating materials, engineers would be able to make more accurate calculations important in a wide range of thermal processes such as heat treating and primary metal production. The Center for Mechanical Engineering and Process Technology is addressing this challenge by preparing a computer program to model the heat flows within these materials. As part of this effort, a computer-controlled "hot wire" technique for measuring thermal conductivity of refractory and insulating materials for furnaces was developed. Less cumbersome and 10 times faster than commercially available techniques, the hot wire method automatically runs tests on the materials. This technique is aiding in the evaluation of a special high temperature Standard Reference Material for industrial testing equipment calibration.

This same NBS center has demonstrated the value of infrared thermography for assessing the energy losses of industrial furnaces and determining appropriate measures to make the furnaces more efficient. Infrared thermography involves use of a device much like a camera which takes photographs showing in different colors the hot and cold spots of the area being

examined. This technique has been used previously by NBS and others to obtain qualitative information about heat leaks and retrofit possibilities in industrial equipment and in buildings.

NBS engineers have now used infrared thermography for the quantitative measurement of heat losses in an industrial furnace, a significant accomplishment. Using an iron-casting foundry furnace, Bureau researchers were able to calculate accurately the amount of heat radiating through the furnace surface and being lost. Currently, engineers typically estimate, rather than measure, radiative heat transfer. With the more precisely calculated information obtained using infrared thermography, engineers computing the heat losses in furnaces can make more informed judgments about possible energy-saving measures.

With or without the advanced

capabilities that infrared thermography offers, such "heat balances" are a fundamental step in any industrial energy conservation program. Last year, NBS prepared and distributed a practical "how-to" guide for performing such calculations: Energy Management for Furnaces, Kilns, and Ovens. (See page 71 for order information.) Cleaner, More Efficient Utilities

In addition to developing methods and standards related to the use of new energy technologies by utilities as part of a major Federal Interagency Energy/Environment Program, NBS also has been active in other ways to bring about cleaner, more efficient utilities.

For instance, the Bureau has been providing the technical base for advancement of the related concept variously known as cogeneration,

integrated energy systems, and MIUS (which stands for Modular Integrated Utility Systems). MIUS-type projects, for example, provide an option to package into a single processing plant two or more of the six utility services necessary for community development (electricity, space and water heating, air conditioning, solid waste processing, wastewater treatment, and residential water purification). Such plants are intended to recover energy that typical ly would be wasted by larger-scale conventional systems and are expected to minimize the environmental impact of utility systems.

NBS analyzed a MIUS "total energy" demonstration plant which provides electricity, heating and cooling to an urban residential/commercial complex in Jersey City, New Jersey. Acting in its role as a neutral, thirdparty evaluator, NBS instrumented the plant and collected the data necessary to evaluate the facility's energy conservation, economics, reliability, and environmental impact. Concluding that the plant is a viable and cost-effective system, the project for the first time provided detailed performance data and a thorough evaluation of an operating total energy plant. This information is needed so that equipment manufacturers, potential users like utilities and industries, government energy policy makers, and regulatory agencies can assess the potential assess the potential benefits and risks of the MIUS concept. The Center for Mechanical Engineering and Process Technology also completed an independent assessment of the design of a Federallyassisted MIUS installation planned for St. Charles, Maryland. Additionally, in its capacity as technical assistant to an international group concerned with the MIUS concept, NBS published an international catalog of more than 200 MIUS-type projects. (For more information on other Bureau energy and environment-related research, see "Safeguarding Environmental Quality," page 54.)

Better Utility Reliability and
Performance

The Bureau has made several recent strides to improve the reliability of electrical power systems and avoid catastrophic breakdowns like the New York City blackout of 1977. The Center for Electronics and Electrical Engineering for the first time measured "Kerr coefficients" of two materials used in electric utility insulation systems. This determination is important because Kerr-effect measurements of electric fields and space charge contribute to a better understanding of phenomena that cause power cables and transformers to break down. These failures can occur either spontaneously over time or as a result of a catastrophic influence, such as lightning in the case of the New York breakdown. This better comprehension of breakdownrelated phenomena is essential in advancing the electricity transmission and distribution technologies needed to accommodate a doubling of present transmission capacity within the next

two decades.

the same NBS group completed a joint In a related project, engineers from

effort with the Bonneville Power Ad

ministration, which serves the Pacific Northwest, to improve the tests which help predict how power systems will react during severe overvoltages. When a system is struck by lightning, for example, power company engineers must know how the power network will be affected. The tests now used to simulate such overvoltages are inadequate because simulated voltage surges cannot be measured accurately. In fact, some materials and equipment might withstand real-life lightning bolts joint research project will now permit but fail existing tests. The results of this

better measurement of simulated

overvoltages and clear the way for more reliable materials and power system performance.

NBS research has increased the technical data base for the Modular Integrated Utility System concept. The "total energy" system demonstration at this Jersey City site was instrumented and analyzed by Bureau engineers.

Also with the aim of improving the performance of electric utility systems, the Center for Materials Science put together a test program to evaluate synthetic porous polymer films for their potential usefulness as insulation in new energy-saving underground power transmission cables. Today, underground cable capacity is limited by the deficiencies of conventional insulation, so the possibilities of polymer insulation substitutes have become important. As part of a cooperative program in this area with DOE and the Electric Power Research Institute, this NBS test program will help measure qualities of the porous polymer insulation material which might lead to electrical discharges and eventual cable failure. This information will be particularly useful to polymer manufacturers in developing products with the insulating properties required by new underground cable systems.

In another project which required expertise in polymer chemistry and high-voltage measurements, NBS assisted DOE's Brookhaven National Laboratory in selecting polymeric tape for electrical insulation in a prototype superconducting power cable which that laboratory is designing for test purposes. Superconducting cables hold great promise as an economical, very high capacity means of underground power distribution. NBS became involved with this research effort since the special facilities needed for making the necessary high precision, low-loss measurements of candidate insulation tapes at cryogenic temperatures and operating voltages were not available elsewhere in the United States.