Casa Aguila Design Review of Power System. V 1.1 - 21-Dec-2014. Status=Complete.

Picture
Summary
The goal of this design review, 1.0, is to afford the builders, Jeff Adams and Rich Williams, as well as the contractors to AGB, a review of Solana's assumptions, dependencies, risks, costs, phases and design approach.

An overarching assumption is a Phased Design. The first phase designs for and estimates both the load profile of the new house and to specify an electrical energy system that exceeds that load by 10% to err on that side of error. In the second phase, the owner would elect to disconnect from the grid and purchase additional hardware and software, especially extra energy storage, so that the house could operate reliably on a grid-disconnected basis. The estimate of power use considered these factors:
  1. The representations of the builders.
  2. The data presented in load profile models.
  3. The power nameplate value of planned appliances.
  4. The EV vehicles charged for personal use.

The working profile for daily average loads is as follows using working ranges:
  • Baseload (Always On: Refrigerators, Freezers, Recirculation Pumps, etc): 24 * 1.0KWH up to 24 * 2.0KWH)
  • On Demand (Lights, AC, Computers, Shop Equipment, Oven, Appliances): 16KWH up to 25KWH
  • EV:  8.5KWH for 25 Miles Per Day (Efficient) up to 30 KWH for 75 Miles Per Day (Less Efficient)

The daily electric load range is 48.5 to 103 KWH Per Day. For the purposes of the current estimate, Solana is working with 100 KWH per day ( 272,971 BTU). This is a working assumption subject to review and further validation. The power system must meet therefore a minimum of 110KWH per day. It does so according to the following quantitative design work:
  1. One (1) Single Vision Air Wind Turbine: 8.3 KWH (Windsun Estimate) or 14 KWH (Solana Estimate) Per Day.
  2. Three (3) Deger D60 Trackers with SunPower Modules: 121 KWH Per Day.
A Sonnen Battery System in three towers provides energy storage of 40KWH to load-shift energy production to times of energy demand when there is insufficient solar or wind resources. In phase one, the SDG&E grid provides energy when all local sources are insufficient to meet current demands.

Schematic of Phase 1 System. View Here.
Notes:
  1. The design calls for three (3) trackers in order to guarantee production well beyond the intended load of the house but accounting for potential unknowns especially in the area of EV charging, AC, and heating. The original design of 30KW of fixed panels is a waste of material. The nameplate value of 22.4KW is more than sufficient.
  2. Joe Moore of WindSun and Dr. Jack Hegenauer and Lane Sharman of Solana provided independent production estimates for the VisionAir5. Since there is a material gap between the two estimates, a determination should be made by the builders for expending further effort on understanding this gap.

Written Summary of Design Requirements and Plan. View Here.

References
Deger Energie D60 Product Specification.
VisionAir5 Product Specification.
SunPower Module Specification.
SonnenBattery Power Specification.
Generac 600-800A Single Phase Transfer Switch Specification.
WindSun VisionAir Proposal Inclusive of Estimates.
Most Recent Adroit Design Proposal.
Design Development Folder.
Energy History at existing McQuillan Residence.