From feasibility studies, route selection, right of way/easement acquisition, and permitting through final design to construction and final inspection, EPS has exceptional capabilities to provide the expertise necessary to successfully complete both underground and overhead transmission projects with distribution, communication and substation components. Our staff’s project experience has varied from sub-transmission through 345 kV and includes a wide range of design and construction approaches. The firm’s experience includes a wide range of voltage levels for new, upgraded, and repaired facilities. Our staff has experience studying feasibility and providing preliminary and final designs for lines with a wide variety of foundation, structure and configuration types. Each project has its own unique challenges, and special designs have been developed for projects with widely varying foundation, climate, and terrain conditions. EPS uses specialized transmission computer programs including SAG10, PLS-CADD, PLS-POLE, PLS-TOWER, PLS-SAPS, CAISSON, and LPILE.

The following is a representative sampling of EPS’s experience and technical competence on transmission and substation projects:

EPS provided transmission engineering services for interconnecting BPA’s South Tacoma 230 kV Substation to Tacoma Power’s new Canyon 230/115 kV Substation. Tubular steel H-frame structures were used for the 230 kV circuit. Additionally, two separate 115 kV lines using steel poles were designed to connect the new substation to Tacoma’s LaGrande double circuit 115 kV line at two tap locations. Drilled pier foundations were used for all the steel structures.

For this project, EPS provided submarine cable design, routing options, cost estimates, cable specifications, and engineering support during construction. Utilities in the state of Washington were interviewed to determine preferences with cable types and manufacturers. Material quotes were solicited from cable manufacturers and cost estimates were prepared for three different options. After Chelan selected an option, drawings and specifications were completed and EPS assisted the District in selecting a cable manufacturer and procuring the cable. A riser structure at the Yacht Club and a pad mounted switch on the Manson side of the lake were also included in the design and construction. Because the existing cable was in relatively good condition, it was kept in service and the new cable was designed around it to provide a redundant feed across the lake.

EPS provided structural analysis services to the District for 13 spans crossing the Columbia River or nearby sloughs that were candidates for adding bird flight diverters (BFDs) to reduce avian collisions. All supporting structures were 230 kV, steel lattice towers ranging in height from 74 to 248 feet. Non-linear, finite element analysis was performed to determine stresses in structure elements and foundations in order to assess if the proposed improvements met the District’s loading criteria.

EPS provided engineering services to the District to upgrade several of their 115 kV lines to use ACSS high-temperature conductor. Four projects totaling over 46 miles in length were field inspected and re-designed for the new, larger conductor. Structures and materials were changed out where required to maintain strength and clearances requirements. The new conductor is designed to operate at 200°C (392°F). The four projects were Rocky Ford – Larson, East Quincy – Rocky Ford, Columbia – Ancient Lake, and Larson – Moses Lake.

EPS provided professional and engineering services necessary to permit, acquire legal access, design and prepare for construction a 115 kV transmission line between the Bernice Lake and Soldotna Substations. The line is approximately seven miles long and includes 25 kV distribution and communication underbuild on wood poles. Sections of the line crossed wet peat bogs, requiring pile foundations. This project required extensive efforts to resolve conflicts between the operational aspects of the Kenai Airport facilities and the project which was located partially on airport lands.

EPS (D&L) is providing full design services for 10 miles of new 115 kV transmission line and expansion of the Redington Substation. The line interconnects Redington Substation with Teeland Substation, replacing a 34.5 kV line. The new line and substation addition are designed and detailed to maintain existing 34.5 kV facilities energized during construction. The line is also designed for upgrading existing distribution underbuild facilities.

When a half mile section of Lincoln Avenue needed to be elevated onto an overpass to relieve freight lane congestion, Tacoma Power retained EPS to relocate several 115 kV and 13.8 kV circuits entering and exiting a nearby substation. New tubular steel poles as tall as 105 feet were used to support transmission, distribution and several secondary and communication circuits. Drilled piers 60 feet in depth were used to support the poles in the former tidal flats area. EPS provided complete transmission engineering including material procurement and on-site inspection.

EPS (D&L) provided complete transmission engineering and construction management for this 57-mile long 138 kV transmission line connecting the Swan Lake and Tyee Lake Hydroelectric projects. The line traverses the extremely rugged and remote terrain of Southeast Alaska. There are four major water crossings, each with a span longer than a mile, the longest being nearly 6,900 feet. The entire transmission line, which included 350 tubular steel structures, was constructed from floating work camps using helicopters. EPS worked with the line contractor to provide value-engineering. These efforts reduced final construction costs by nearly 20% from other design teams.

The Diamond Ridge Substation is a 115 kV main and transfer bus station with a 115 kV/ 69 subtransmission transformer and a 15 / 24.9 kVdistribution station transformer. The station serves as a critical switching station as well as a critical distribution source for the Homer area loads. The 115 kV main and transfer bus encompasses six breakers and utilizes SEL 487, SEL 311C and SEL-421 protective relays and an SEL-3354 for station automation. The distribution station includes 5 breakers and SEL-351S relays, SEL-487 relays and an SEL-3354 for station automation. The station was designed for extreme snow conditions that have been observed in the area. The project included extensive site work due to poor soil and permafrost conditions.

EPS completed the design and construction inspection for the new Retherford Substation in Anchorage. The substation consisted of two 100 MVA transformers, two 138 kV breaker and one-half bays and thirteen 34.5 kV breakers configured in a main and transfer bus scheme in metal-clad switchgear. EPS was responsible for the design of the substation civil work, bus layout, grounding and lighting. EPS was responsible for the design of the protective relay installation for the transmission lines, transformers and 34.5 kV feeders. EPS was responsible for the communications and SCADA interface with the Chugach control center. EPC completed the electrical testing and commissioning for the construction contractor. EPS completed the quality control inspection for the substation construction.

EPS completed the design and construction inspection for the new Postmark substation in Anchorage. The substation consisted of two 14 MVA transformers, two 138 kV breakers and nine 12.47 kV breakers configured in a main and transfer bus scheme with a double-ended bus arrangement in metal-clad switchgear. EPS was responsible for the design of the substation civil work, bus layout, grounding, and lighting. EPS was responsible for the switchgear specifications and protective relaying arrangement. EPS completed the quality control inspection for the substation construction.

EPS completed the design and construction inspection of the new Woodinville BP/Olympic station near Bothell, Washington. The substation consisted of four 4.16 kV feeders in metal-clad switchgear. The construction and commissioning of the substation was required to be completed within a single four day outage, and the design accommodated this restriction by pre-constructing a significant portion of the station prior to the outage.

EPS was responsible for the switchgear design and specifications, station layout and civil work, protective relaying settings, medium voltage and low voltage design, and arc flash calculations. EPS completed the quality control inspection, and all testing, commission, and startup for the substation construction.

EPS completed the civil, structural and electrical design for the 34.5 / 12.47 kV Airai Substation. Project included concrete block control building, relaying and control panels, four 12.47 kV breakers, installation of controls and modifications for one 34.5 kV breaker and three 34.5 kV motor-operated switches and SCADA control and monitoring for the station. EPS provided the structure design, electrical service, grounding, protective relaying and controls design. EPS completed the installation and commissioning.

EPS provided structural engineering to add a new bank to this existing substation. It included adding a new 230 kV, 400 MVA power transformer and new 230 kV deadend structures. Existing lattice steel deadend structures were analyzed for attaching the new bay, and steel procurement documents were developed for the new structure. The transformer foundation was designed for High Seismic Level in accordance with IEEE 693-2005.

Electric Power Systems’ SCADA project experience includes:

SCADA System Engineering, Procurement and Construction

The City of Soldotna desired to upgrade their existing control system, which was limited due to age, technology employed, and the number of sites at which it was deployed. EPS teamed with the prime contractor AirTek of Soldotna to provide the City a new SCADA system. EPS performed all of the design engineering for the electrical installation and the UL 508A control panels. In addition, EPS provided the materials for the control system, including a Wonderware HMI (human-machine interface), four GE 90-30 PLC’s for the well sites and reservoir, and the 920 MHz radio system to allow the remote sites to communicate with the HMI at the treatment plant. EPS programmed the PLC’s and HMI, assisted AirTek with construction-related engineering, and provided final startup, commissioning, and training for the Owner. EPS staff worked with the electrical contractor as a subcontractor, while keeping the goals of the owner in mind. The project was completed on time and budget, with only minor changes required from the original design. EPS has maintained a working relationship with both the owner and the contractor in the ensuing years. In fact, EPS continues to work for the City upgrading and adding facilities to their SCADA system. Since the completion of this project, EPS has added two additional wells and one reservoir, and has discussed the costs and requirements for adding the waste water facilities into the system.

Kotzebue Switchgear and SCADA System Upgrades

Kotzebue is a remote hub-community that is electrically isolated from any other system. The community runs predominantly on diesel and windpower. The windpower installation consists of 14 turbines, located on the edge of town. The project consisted of completing a design for the switchgear, SCADA, and mechanical/electrical instrumentation systems. Following completion of the design and acceptance by the Owner, the construction phase of the project commenced, installing all of the switchgear and controls in a phased manner to allow continuing plant operation. The project included system automation to monitor remote equipment and turbine status, automatic control of generation and loads to optimize the economics of the wind integration.

Orca Power Plant Automation

The Orca power plant is the primary control point of Cordova Electric Cooperative’s (CEC) entire generation and distribution system. From the control room at the ORCA plant operations monitor and control 5 diesel units at the ORCA plant, 2 hydro units at the Power Creek plant and 3 hydro units at the Humpback Creek plant. Operations can also monitor and control feeder breakers at the Eyak substation. With this SCADA system operators can manually control all generation units, distribution feeders and dam operations as well as monitor the status of all critical dam, unit and feeder details from one central location. The Cordova SCADA system also features “Demand Control” which allows the SCADA system to make all decisions and necessary adjustments to the electric utility system to maintain a steady, clean and reliable supply of power for the city of Cordova and the surrounding area. The main focus of Demand Control is to provide the most efficient use of the available hydroelectric power, keeping the use of diesel units to an absolute minimum. This control system also allows operations to “unman” the control room after normal working hours. An automatic callout system will alert operations to any deviances from normal operations.

Mountain Top Power Modules

EPS designed and constructed multiple modules to provide power to communications equipment for remote mountaintop microwave facilities in western Alaska for United Utilities. The power module consists of two diesel 10kW generators with two bulk diesel tanks feeding the day tank. The SCADA system is utilized for remote monitoring, control of the generators to charge the battery system and HVAC for the power and communication module. The SCADA architecture consists of one PLC per generator, one PLC for system and ancillary I/O, and redundant servers for data collection and remote access. The PLC’s will maintain the module room temperature and adequate combustion air for the engines. The two generators are redundant units, and the SCADA system will select which unit will run based on availability. The SCADA system will notify UUI in the event of an alarm that requires attention from an operator.

Eklutna 230 kV Transmission Line Re-build

This rebuild of the Eklutna Transmission Line between the power-generation facility near Eklutna Lake and Fossil Creek near Fort Richardson, took it from its 1950 configuration as a wood pole H-Frame 115 kV single circuit line to a 230 kV double circuit line on single steel poles. All existing rights of way for the 22.5 mile line required review and a determination if the existing grants authorized the upgrade. Property interests on 96 properties were analyzed resulting in the identification and acquisition of additional easement rights for 45 parcels, and the acquisition of 3 parcels for a 3 mile re-alignment. The project was controversial due to a disgruntled minority co-owner of the project. A major public involvement effort for the right of way process before the local communities was required as a result of the actions of the co-owner. Despite the co-owner’s actions, rights of way were acquired without resorting to eminent domain and a contested Bureau of Land Management right of way was granted after an appeal to the Interior Board of Land Appeals. Easements were obtained across a military base, municipal park lands, as well as lands under the jurisdiction of the Alaska Department of Natural Resources. A SWPPP was prepared and permits were acquired from the Federal Aviation Administration (FAA), U.S. Army Corps of Engineers (USACE), Municipality of Anchorage (MOA), and the Alaska Department of Transportation (DOT).

O’Malley 138 kV Transmission Line and 12.5 kV and 34.5 kV Underground

The improvements included burying a 12.5 kV and 34.5 kV circuit, and construction of a new overhead 138 kV circuit. This project involved the route analysis, cost estimating, value estimating, administration of surveying, parcel platting, SWPPP preparation, and environmental stipulation compliance, title examination, regulatory permitting and the acquisition and purchase of 14 transmission line parcels, 22 underground distribution line parcels, and six temporary construction easements, as well as notifications to all adjacent property owners along the route including 15 with service drop changeovers. One parcel required an appraisal and condemnation. Permits were obtained from the Alaska Railroad Corporation, the DOT, MOA, Alaska Department of Environmental Conservation, and USACE.

69 kV Marathon to Ivanoff Lake Intertie

EPS (D&L) provided professional and engineering services necessary to permit, acquire legal access, design and prepare for construction a nominal 69 kV / 115 kV transmission line that created a double-ended transmission system between Bernice Lake and Soldotna Substations. This project required extensive efforts to resolve conflicts between the operational aspects of the Kenai Airport facilities and the project which was located partially on airport lands. EPS obtained all regulatory permits required by the FAA, USACE, Kenai Peninsula Borough, DOT, State of Alaska Department of Natural Resources and the City of Kenai. Appraisals were performed for key parcels in aid of acquisition of agency owned properties, Alaska Native Corporations and private individuals. A total of eight individual parcels were acquired based on the appraised valuations.