Access to electricity remains elusive for over 700 million people worldwide. Although much attention has been given to solving this vexing problem in the context of communities in Sub-Saharan Africa and South Asia, often overlooked is that in even within so-called developed countries access to electricity might not be universal. It is estimated that more than 200,000 people living in North America do not have a connection to the electric grid. Many of these people live on Native American reservations or other Tribal Lands. Recently, there has been a concerted effort in the public, private, and non-profit sectors to electrify these homes with off-grid solar systems. This paper analyzes the electrical energy usage characteristics of 127 homes on the Navajo reservation in the southwestern United States. The homes have identical 3.8 kW solar arrays, 35.1 kWh 48 V gel lead acid battery banks, and 8 kW inverters. High-resolution inverter data was collected from these systems for a two-year period. Several statistical analyses were conducted on the data, including computing the statistical moments, creating empirical distributions of daily consumption, and analyzing consumption variation across different timescales. The results show average consumption of 2.78 kWh per day, but with a wide range of variation among homes. The implications of the analyses on pre-implementation system design, post-implementation interventions, and comparisons to incipient electricity consumption characteristics elsewhere in the world are discussed. The use of the average daily consumption in data-driven load estimation is evaluated and found to offer promising improvements over survey-based methods.
Louie, Henry; Atcitty, Stanley; Terry, Derrick; Lee, Darrick; and Romine, Peter, "Daily Electrical Energy Consumption Characteristics and Design Implications for Off-Grid Homes on the Navajo Nation" (2023). Electrical & Computer Engineering Faculty Scholarship. 2.