Distributed Renewable Energy Operating Impacts and Valuation Study

EXECUTIVE SUMMARY
Abundant sunshine and broad
support for solar energy
combine to create outstanding
opportunities for solar
technology deployment and
value for all stakeholders.
Background and Objectives
Arizona is richly endowed with solar resources. Arizona is
also one of 28 states seeking to increase the amount of
renewable resources in its state energy supply portfolio
through Renewable Energy Standards (RES). This program,
like those in other states, promulgates regulatory policies that
require electric utilities to increase the production of electricity
from renewable energy sources including wind, solar, biomass
and geothermal energies. The abundant sunshine and broad
interest and support for solar energy combine to create
outstanding opportunity for solar technologies to be broadly
utilized in the state.
Much attention is focused on development of large-scale solar
installations. These utility scale projects capture media
attention for their size and scale, and often for cutting edge
technology. They are single-site projects that can add valuable
renewable energy resources to the energy supply. Another
technology category, distributed energy (DE), harvests value
from broad scale deployments of much smaller installations.
This is the domain of individual residential and business
customers who install solar technologies on their rooftops to
serve part or all of their own electrical energy during the day.
Indeed, Arizona’s RES calls for 15 percent of the retail electric
load to be met with renewable energy resources and 30 percent
of that amount to be met with distributed energy, as indicated
in the graphic on the following page.
Large-scale deployment of DE is a relatively new concept and
there are myriad complexities and implications associated with
installing distributed solar generation (referred to herein as solar
DE) broadly across a utility electrical system. The opportunity
for broad solar deployment is matched by the complexity of the
technical issues and the continuously changing solar
technologies. The Study sought to create a factually based
common understanding of the specific implications of solar DE
on the Arizona Public Service (APS) system.
© 2009 by R. W. Beck, Inc. All rights reserved.
Arizona Public Service