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Mr. HENLOCK. Yes, sir; and might I add that we have therefore lived within an authorization made in 1958, which we feel was well forecast by Mr. Rubel at that time for a long-range project.
Mr. ANDREWS. What would happen if the committee did not see fit to grant this request! What would be the consequences ?
Mr. RUBEL. It probably would result in a delay in awarding of some future contracts. The work should be continued uninterruptedly so that we can get the current expansion program completed. We can see another big expansion program coming up to accommodate the new Library Building load. The third Library Building will impose a substantial new load on the refrigeration plant. We must soon start work on that project and therefore it would be advisable to complete the current program as soon as possible. Mr. ANDREWS. Do you have any opinion about what that would cost? Mr. RUBEL. The next one? Mr. ANDREWS. Yes.. Mr. RUBEL. Between $8 and $10 million. Mr. ANDREWS. Just for the Library? Mr. RUBEL. It is more than that, sir. The estimate we now have from the associate architects for the new Library Building is that it will require 5,300 tons of refrigeration. That quantity is one-third of the present installed capacity at the plant. In addition to that, it is conceivable that the New Senate Office Building will be expanded within the next few years and that will add another load of 1,500 tons. Also it is probable that the west front eventually will be reconstructed and that would add another 1,500 tons.
Mr. ANDREWS. The more space you get on Capitol Hill, the bigger the burden placed on your plant down there.
Mr. RUBEL. This is true with all utility plants. They are growing every year. Mr. ANDREWS. Do you finance wornout machinery out of this fund?
Mr. RUBEL. Yes, sir. We are in the process right now of replacing The stokers under the three large coal-fired boilers. You provided us last year with an appropriation of $45,000 for the first phase of that work. One of the old stokers is just about to be dismantled and we expect the new parts to arrive by May 15.
Mr. HENLOCK. That work is being done under our regular annual appropriation and not under the expansion of facilities project appropriation. Mr. RUBEL. We will have two more stokers to replace.
Mr. ANDREWS. Could you put in the record at this point the total cost of the operation of the Capitol Power Plant, everything? Mr. RUBEL. Do you mean the annual operating cost ? Mr. ANDREWS. Yes. Mr. HENLOCK. Actually the $2,841,600 which we are asking for 1968 is what it takes to run the plant annually.
Mr. ANDREWS. Are there any questions on expansion of facilities, Capitol Power Plant?
HISTORY OF PLANT Mr. HENLOCK. Mr. Stewart has had a historical report prepared and we would like to see it in the record. It is a 20-page history of the Capitol Power Plant from its origin in 1910, showing how it was originally a powerplant, what it is today, what changes have occurred during the years and what its present status is.
Mr. ANDREWS. That might be interesting, and without objection, we
(The document follows:)
ARCHITECT OF THE CAPITOL, WASHINGTON, D.C.
(A) Removal of obsolete equipment.
Map of Capitol Hill area, including power plant and river pump house.
CAPITOL POWER PLANT-ORIGIN AND INITIAL FUNCTIONS
During the development of the plans at the beginning of the 20th century
Having determined the feasibility of a central power plant, a site was selected
Authorization for the construction of the Capitol Power Plant was enacted on
Steam for heating and electricity for lighting and other services were dis-
the Congressional Library Building were served from the tunnel on First Street through branch connections terminating in those buildings.
Alternating-current electricity generated at 6600 volts and having an electrical frequency of 25-cycles was distributed from the Power Plant to the buildings heretofore mentioned by way of a network of sub-surface conduit and cables constructed and operated by the Federal Government. The 6600-volt, 25-cycle electrical energy generated at the Plant and distributed through the underground cable network was transformed in the several buildings to low-voltage energy (230 volts) for utilization by 25-cycle motor-driven equipment and, additionally, it was converted to direct-current energy by means of rotary convertors, with several convertors located in each building. This direct-current energy was the source of power for the extensive incandescent lighting systems in vogue at that time, and for numerous direct-current motors already in operation in the Capitol and the Congressional Library Building.
In the ensuing years, additional buildings were added to the plant's load. There were added to the steam and electrical load of the plant in 1922 the Government Printing Office and the Washington City Post Office; in 1932, the Legislative Garage, now known as the Senate Garage; in 1933, the First Street Wing of the Old Senate Office Building, the Longworth House Office Building, and the New Conservatory and other Botanic Garden Buildings; in 1934, the l'oited States Supreme Court Building; in 1938, the Annex to the Library of Congress. Necessary extensions to the steam and electrical distribution systems were made to connect these buildings to the plant's load. These buildings were added to the plant's load, prior to changes and improvements effected at the Capitol Power Plant in its steam and distribution systems under a modernization program authorized by Congress in 1916, and also prior to establishment and operation of the refrigeration plant at the Capitol Power Plant in November 1:38. All of these buildings are still being served by the Capitol Power Plant. The only permanent service discontinued prior to the 1946 modernization program was the furnishing of electrical service to the Government Printing Office and the Washington City Post Office, which service was discontinued in 1937.
The Capitol Power Plant, equipped as heretofore described, was originally placed in operation in 1910. House Report No. 2291, 61st Congress, 3d Session, states that:
-The design and construction of the Power House was entrusted to the Superintendent of Construction, with the same direction and supervision of the Commission as that exercised with respect to the House Office Building, and the architectural design was prepared in the Office of the Superintendent.
The resulting building is of simple design, constructed of red brick, intended the future to be stuccoed and otherwise treated by planting, in the near vicinity, w that when the development of the park is completed the building will not be bjectionable. It is sufficiently large, not only to accommodate the equipment requisite for the service of the four buildings now constructed, but to meet the memands of any other building or buildings that may hereafter be constructed ast of the Capitol Plaza. "The arrangement of its mechanical detail is such that continuity of service oder all conditions is practically assured, there being sufficient duplication of apparatus to meet the conditions which surround the operations of a plant devoted to this peculiar service. It should be noted that the service required is wholly different from that usually demanded of an ordinary commercial plant. Suitable suhstations have been installed in the several buildings to take care of the indiridnal building loads required, and arrangements are being provided so that during the recesses of Congress one or two of the substations alone can take fare of the necessary distribution to and from the several buildings, namely, the Capitol, the Honse and Senate Office Buildings, and the Congressional Library Bnilding. The main lines of transmission run from the Power Plant to the several huildings through the medium of a long subway approximately 6200 feet in total length, the size of the principal tunnels being 7 feet in height by 4 feet 6 inches in width, affording easy inspection at all times.
The total cost of the Power Plant, embracing necessary machinery, transmission systems, substations in the several buildings, and a special waterway from the plant to the river, including appropriations made at the present session of Congress, is $1.545.975.65."
From the time of its inception the predominating objectives associated with the Canitni Power Plant have been the assurance of reliability and continuity of service. These fundamental ideas have been persistently observed in the design
of all later additions and improvements. The validity of this procedure has been confirmed by the Plant's uninterrupted service record for over one-half century.
Toward the close of the 19th century, the Capitol and the Congressional Library were both wired for 110-volt direct-current electricity, and numerous directcurrent motors were in use in these buildings. If direct current had not been sup plied to these buildings at the time when the central plant idea was conceived, expensive alterations would have been inescapable. Therefore it was decided to retain this system in the existing buildings and to install the same type of system in new buildings to assure similarity of equipment and operation in all the buildings. The maximum transmission distance, being approximately 34 of a mile from the Power Plant to the Senate Office Building, dictated the use of alternating current at relatively high voltage for transmission.
Accordingly, it was decided to generate and transmit alternating current at 6600 volts, and to install several motor-generator sets in the buildings served by the Plant to convert the transmitted alternating-current energy to low-voltage direct-current energy. Electrical energy also had to be furnished for the motordriven equipment in the pump house on the bank of the Anacostia river, slightly less than one mile removed from the Plant. The fact that 25-cycle power was available prior to 1910 from the Benning Plant of the Potomac Electric Power Company provided the Government with the opportunity to purchase energy from that company to activate the building substations in advance of the completion of the Capitol Power Plant.
The original boiler plant equipment consisted of 16 water-tube boilers each rated 520 boiler-horsepower when operating at 175 pounds steam pressure. These boilers were arranged in two rows of eight units on both sides of a central operating aisle. The Atlas Engine & Boiler Works of Indianapolis manufactured this equipment. Each boiler was equipped with a Roney automatic stoker designed for bituminous coal utilization. The boiler-feed water was taken directly from the city mains, from the river, or from the hot well in the plant. The city water was fed to the boilers by Metropolitan injectors, each boiler having an independent injector. Boiler-feed water taken directly from the hot well was fed to the boilers by Warren high pressure, plunger-type pumps. The ashes from the furnaces dropped by gravity into large hoppers directly beneath the boilers. Manuallypropelled cars running on narrow gauge tracks located directly under each row of hoppers collected the ashes and transferred them to the south end of the build. ing. At this point an elevator conveyed the ashes to an elevated storage hopper. Periodically the collected ashes were discharged through iron chutes into the railroad cars beneath the storage hopper.
The electrical generating equipment consisted of four Westinghouse-Parsons turbo-alternators, each rated 2,000 kilowatts, and delivering 3-phase, 25-cycle alternating-current at 6600 volts. The steam turbines operated at 175 pounds steam pressure and the steam, after passing through the turbines, discharged into barometric condensers guaranteed to produce a vacuum of 28 inches when supplied with injection water at a temperature of 70° F. The condensed steam discharged into a hot well and subsequently was pumped to the boilers to complete the thermal cycle.
In 1923 the 16 original boilers were replaced by Babcock & Wilcox cross-drum water-tube boilers rated at 510 horsepower each. These boilers were equipped with Westinghouse underfeed, multiple-retort stokers. Subsequently two of the 2,000 kilowatt turbo-generators were replaced by two DeLaval steam turbogenerators rated 6,250 KW each.
The 16 Babcock & Wilcox boilers, two of the original 2,000-kilowatt Westinghouse turbo-generators and the two 6,250-kilowatt DeLaval turbo-generators were retained in operation until 1951. In 1932 a skip hoist for handling coal from the railroad cars to a newly-created storage yard was placed in operation and the original bucket elevator, which still exists at the south end of the boiler house. was retired from service. The original turbine room building and its contiguous electrical bay, the north half of the original boiler house and the two brick stacks. all completed in 1910, are still in use. In 1952 the south half of the boiler house was reconstructed on its original foundations to accommodate the three large coal-fired steam generators which now supply the major portion of the greatly expanded steam load.
Developments attributable to the introduction of air conditioning, the advancements in the electrical industry, and the load growth brought about by the construction in recent years of new buildings are described in Parts II, III and IV of this report,
INTRODUCTION OF REFRIGERATION FACILITIES
When the Capitol, Senate Office Building and two House Office Buildings were air-conditioned in 1936–38 at the direction of Congress, a new structure measuring 123 feet long, 79 feet wide and 38 feet high was built at the Capitol Power Plant to house refrigeration apparatus having a total capacity of 4800 tonsa ton of refrigeration being the equivalent of the heat absorbed by the melting of 1 ton of ice in 24 hours. This structure, still being used as a refrigeration apparatus room, is a three-sided brick building annexed to the easterly end of the turbine room built in 1907-10. The turbine room wall is common to both sreas.
The equipment installed in the new refrigeration apparatus room included six 800-ton freon-12 reciprocating compressors, each driven by a 1,000 HP synchronous motor; six water coolers having a capacity of 800 tons each ; thirty-six freon condensers having a capacity of 150 tons each; two 4,000 gallon-per-minute chilled water pumps driven by steam turbines of 800 HP each; two surface condensers for the steam-turbine-driven chilled water pumps; and the necessary freon piping, chilled water piping, condenser water piping, steam and exhaust piping.
Under the same project, two 12,000 gallon-per-minute centrifugal booster pumps, each driven by a 500 HP., 6600-volt, 25-cycle motor, were installed in the basement of the turbine room to augment the supply of river water to the freon condensers located in the new refrigeration apparatus room, and also to serve the steam condensers associated with the turbine-driven electric generators located on the operating floor level of the turbine room.
Electrical energy for the 1000 HP compressor motors and 500 HP booster pump motors was supplied at 6600 volts by the 25-cycle generators also serving the Capitol Hill 6600-volt electrical distribution system.
Chilled water at 40° F produced by the six water coolers associated with the Dew refrigeration apparatus was pumped to the Capitol, the Senate Office Building and the two House Office Buildings by means of the new chilled water circalating pumps through underground supply and return mains, varying in size from 24 inches to 12 inches, for a distance of more than 34 of a mile each way. Absorption by this circulated water of the excess heat in the buildings connected to the underground piping system caused its temperature to rise from 40° F to approximately 52° F during its circuitous route from and to the refrigeration apparatus.
Upon return to the refrigeration apparatus at the Capitol Power Plant, the water was re-cooled to 40° F and pumped back to the buildings for reuse in their air cooling equipment. So long as the refrigeration and pumping apparatus at the Capitol Power Plant was in operation, this repetitious cycle of water flow and temperature change was continuous and effective in maintaining satisfactory rironmental conditions in the Capitol and the Legislative Office Buildings.
This new refrigeration plant and its associated pumping facilities was placed I operation on May 16, 1938, and was, at that time, the largest central station rater-cooling plant ever constructed in the United States. The identical principle of operation is employed today by the Capitol Power Plant but the capacity of the refrigeration plant facilities has been increased more than threefold, without
o building construction, under the projects described in Parts III and IV of this report.
CHANGES AND IMPROVEMENTS AUTHORIZED BY PUBLIC LAW 413 In the decade preceding the authorization in 1904 for the construction of the Capitol Power Plant, the relative advantages of direct-current versus alternatingcurrent electricity as sources of energy for illumination and power utilization was a topic of heated controversy among competent engineers such as George Westinghouse, Thomas A. Edison, Nikola Tesla and others.
The easy transformation from lower to higher voltages developed by Nikola Tesa, and the economies inherent in the transmission of higher voltage currents were formidable arguments propounded by the advocates of the use of alternating current electricity. The disadvantage of varying instantaneous magnitudes of current, with zero values of current flow occurring as the direction changed periodically from positive to negative flow, was a strong argument in favor of the continued use of direct current electricity as exemplified by the Pearl Street Electric