Current HQ Energy Usage

Tyson’s existing solar array isn’t quite enough.

The current 50 kW ground-mount array feeds both the HQ building and the lab. While significantly reducing their net consumption from the grid, Tyson’s goal of net-zero energy requires more generation than they have now.

Initial Solar Layout

Aurora is an industry-grade software used to create layouts of solar arrays and offer an initial idea of how the system will be interconnected. The images below show the panel layout with interconnections and its predicted performance.

Aurora provides a preliminary prediction of performance. A more detailed simulation was found using the NREL software, System Advisory Model (SAM).

Final Solar Layout

After discussion with Tyson and EFS Energy, we concluded that the simplest and most cost-efficient solution would be to place all of the panels on the ground in a plot of land just west of the HQ building. All of the Dynoraxx flat-roof racking can also be used as ground mount. Installation is much easier using one racking system rather than two. A model of this proposed layout was done using Helioscope, a software similar to Aurora, as a way to visualize the new proposed layout.

Inventory & Building Loads

Equipment Inventory & Budget

Most of the project equipment was inherited from the CRETE House project. The project still requires some additional material that will need to be purchased as well as engineering and design costs.

Item  Add. Info Price Before Tax Source
Tesla Powerwall 2 AC $0/item x 1 = $0.00 From CRETE House
SolarEdge Electricity Meter $0/item x 1 = $0.00 From CRETE House
SolarEdge Inverters (7600W and 3600W)   Includes Auto Transfer Switch $0/item x 3 = $0.00 From CRETE House
SunPower Solar Panel $0/item x 31 = $0.00 From CRETE House
Dynoraxx Racking 2-Leg Baskets $0/item x 12 = $0.00 From CRETE House
4-Leg Baskets $0/item x 36 = $0.00 From CRETE House
PV System Components
SolarEdge DC Power Optimizers SolarEdge P400 ($0/item x 27) + ($71/item x 3) = $213.00 From CRETE House and to be purchased from Wholesale Solar
SDC Disconnect for Ground Mount System 4P/30A/600V DC $350/item x 1 = $350 From
Wire (Panels –> Inverter) 10 AWG Wire $89.99/250ft * 2 strings = $179.98 From
Wire (Inverter –> Main Panel) 8 AWG Wire $0.37/ft x 50ft = $18.50 Estimated 25 ft from inverter to panel in basement
Conduit (Ground Mount –> HQ) 3/4″ PVC $2.59/10ft * 250ft = $64.75 From The Home Depot
Conduit (LLC, HQ Indoor) 1″ EMT $10.40/10ft * 100ft = $104 From The Home Depot
Engineering Costs
Engineering Fee for DynoRaxx design Ballast Plan Redesign $100/design x 1 = $100 From DynoRaxx Design Team
Electrical Installation by Contractor Solar & Powerwall Installations $82.08/hr * 20hrs = $1313.28 From Missouri average cost for commercial electrician
Total: $2343.51

LLC Building Loads

We discussed critical loads that would be of interest in this building, listed in the table below, and used device specifications or educated estimates of power consumption for each load. 

Critical Load Description Power (W) Product ID
Compost Exhaust Fan Toilet exhaust fan 71 Fantech FR 150
LLC UPS 21144 UPS Battery System – Fully charged idle power 10 GXT4-6000RT208
UPS PDU PDU for UPS System 5 AP7811B
House PDU PDU for house load 5 AP7811B
TYS-MAINHOUSE-WU-SW-0 Network switch 101.5 (max) WS-C3650-48PD
Conference Room Lighting/Fans 4 Fans (87W ea), with LED lights(17.5W ea) 418 HD-1994 BD E81964 82H4 (ZS)
Fire Alarm Panel Fire Alarm Annunciators & Control Board 91.2 Simplex 4008
Fire Smoke Dampers Mechanical Smoke Damper 9 Johnson Controls H2000/6 (estimated model)