1. Decommissioning Existing Facility a. Responsibility for removal and disposal is as follows: i. Bidder initiates shut down of the existing system with DNR coordination. ii. DNR all (112) lead-acid batteries. iii. Bidder existing inverters and balance of system equipment in the Caretaker Basement. iv. Bidder existing PV shingles. v. DNR will be responsible for rooftop shingle repairs. 2. Power Integration: a. Bidder will replace the 2-phase Caretaker Cabin panelboard and Distribution Panelboard with 3- phase panelboards and satisfactorily balance loads across all three phases. The contemporary assumption is the existing conduit sizes between buildings will be sufficient for the new system, though cables may need replacement (such as from AL to CU). b. The new system shall be DC-coupled with PV and Li-LFP batteries only. The new inverters should allow for future integration of a fossil fuel generator as an additional AC terminal option. c. Presently there is no active winter load. The new winter electrical load will include tare losses from the new off-grid system, a weather station, satellite internet connection, and new electric heaters designed to ensure the basement maintains a temperature above the new equipment’s minimal design temperature thresholds. d. With (2) new inverters, Bidder will be required to install a new additional AC balance of system equipment including an AC combiner/panelboard. 3. PV Array Layout: a. Minimum 30 degree fixed-tilt, 2-high modules in portrait, min 3’ from ground. b. Bifacial, Tier 1 modules, or equivalent. c. Rack foundations: Due to potential for shallow rock or mineral deposits, DNR preference is a ballasted solution that does require ground penetrations as deep as ground screws or pounded posts. NRTL certified solutions such as gabion baskets may be considered. 4. Land Constraints: There are negligible known land constraints for the anticipated PV array size. 5. Land Maintenance: Area with and around the PV array, and vegetation that may cause shading will be maintained by DNR staff. 6. Shade Details: No major obstructions expected. 7. Fence Requirements: No permanent fence required around PV array. Bidder should describe a solution for minimizing exposed wire at the array as risk mitigation from the general public and animals. 8. Underground Utilities: DNR anticipates minimal existing underground utilities, with the exception of water lines near the Well Pumphouse.
