a literature review: analysis of renewable energy
TRANSCRIPT
Sarah Egener April 9, 2015 ENVS 3020
A Literature Review:
Analysis of Renewable Energy Portfolio Standards in the U.S.
Abstract A review of literature examining renewable energy portfolio standards in the United States. Through meticulous evaluation of journals, this literature review examines the findings and methods of previous studies regarding these renewable energy standards. By setting the scene with a background in the standards, meaning their history and design, this literature review then delves into what types of trends, impacts, costs, benefits, and alternatives of renewable portfolio standards have presented thus far in their existence. The data incorporated in this review comes from a variety of research methods, including social, economic, and statistical perspectives. With a firm grasp on the current status of renewable portfolio standards in the United States, this review of literature then prompts further research within the question of whether a federal portfolio standard is feasible and down a path worth exploring for our nation and its renewable future. Introduction It has been quite difficult for the United States to take real action and incorporate renewable
energy sources into viable usage. Within this lackadaisical mindset sprouted some new standards that
would eventually pick up speed and prove to make substantial progress into our modern day. Renewable
portfolio standards (RPS’s) have emerged as one of the most important policy drivers of renewable
energy capacity expansion in the U.S. They are a type of legislation that cracks down on environmental
initiatives and works with the economic sector in order to get renewable energy generation on the
electrical grid once and for all, all at the state level. With all of the attempts to increase renewables that
have not made substantial progress, could renewable portfolio standards finally be that regulation that
puts forth real results? This literature review aims to investigate some of the many internal and external
factors associated with renewable portfolio standards including trends, impacts, costs, benefits, and the
alternative of feed-in tariffs through previous studies done by credible researchers. With the
accumulation of prior literature this review aims to assess the current status of RPSs and where the
United States stands in terms of a federal standard that applies to all different types of states with
varying resources, finances, utilities, ideologies, and more.
Background Design Renewable energy portfolio standards (RPSs) are pieces of legislation that require retail power
suppliers to purchase a certain amount of renewable energy credits or certificates (RECs) in proportion
it its total kilowatt-hour (kWh) energy sales. These RECs are energy commodities that only pertain to
the U.S. and provide evidence that 1 kWh was generated from a renewable energy source. They are
intangible yet tradable, and are basically the monetary system involved when hitting those renewable
energy standards. Retail suppliers can certify their own RECs through their own renewable facilities or
purchase RECs from other facilities directly from renewable generation or a REC broker (Rader, 1996).
Agstar additionally examines the RPS in an unbiased manner by delivering the key features of the
standards and the requirements that they necessitate. The goals of RPS can be environmental, economic,
technological, etc. and range from local to global scales. RPS applicability is most commonly applied to
investor-owned utilities and electric service providers. While municipal and cooperative utilities are
self-regulated, states have made specific revisions to their RPS’s to allow municipalities and
cooperatives to voluntarily adopt the standards. Eligibility for RPS depends on geographical location,
resources, technologies, facilities, and whether they align with goals (Agstar, 2014). Anthony Paul, a
colleague of later literature author Karen Palmer, outlines how RPS policy is modeled with targets,
timetables, and compliance payments. He actually compares the RPS design to the American Clean
Energy and Security Act of 2009 (H.R. 2454). Whereas this bill allows for energy savings from
investments to count towards the standard, RPS’s do not include this feature in their design and instead
involves alternate compliance payments, which is an extremely important aspect (Paul, 2011).
History Gonzalo Frances analyzes the conditions leading up to RPS construction and development. With
a perspective concerning preconditions, Frances studies how environmental issues of the 20st century
allowed renewables to gain momentum. Many pollution and climate change concerns slipped into the
realm of public awareness and encouraged governmental policies. Renewable energy source promotion
along with energy efficiency measure would combine into many of the policies we know and use today.
As a result, Frances concludes that these efforts are what have instilled renewable development since the
start of the 21st century have been great. Though Frances delves into RPS’s in his study, he focuses
mainly on policies as a whole (Frances, 2013). Christopher Namovicz from the Electricity Journal
discloses RPS origin in his studies. Thoughts and design of RPS’s first sprung up in California in 1995.
With its actual implantation in 2002, renewable energy advocates across the country started expressing
their desire for similar standards everywhere. Through stand-alone legislation, one by one states have
adopted their own RPS versions. Namovicz refers to this process as “market-friendly” because it is a
requirement that does not allocate lots of government funding. He includes a visual chart in his study
that not only portrays state enactments of RPS’s but also illustrates any revisions made throughout RPS
history, and this can be seen below. Through text and visuals, this literature author introduces RPS’s
through understandable description (Namovicz, 2007).
(Namovicz, 2007)
Current Status 29 states and the District of Columbia to have mandatory renewable requirements within their
total generation and 8 states to have goals for mandatory requirements in the process, and this can be
visualized with the percentage of total generation and by what year in the image below (Jenkins, 2013).
These RPS’s are present in both restructured electricity markets and in cost-of-service-regulated markets
So far, no state has gone back and repealed any of their RPS legislation that has already been enacted. In
fact, RPS’s that have not gone untouched have only been strengthened by raising the percentage of
renewable energy produced within the overall generation. Though this literature focuses solely on the
United States, there are renewable mandates across the world in forms of quotas, obligations, certificate
programs and more in nations such as the U.K., Sweden, Belgium, Italy, Poland, Japan, Australia, and
more (Wiser, 2014).
(Jenkins, 2013)
Summary of Research Trends Jess Chandler from Science Direct’s Energy Policy Journal examines the trends in which states
adopt RPS while considering their diverging internal circumstances as well as external innovation.
Through statistical analysis of logistic regression, Chandler examines many independent variables
against the independent variable: renewable portfolio standards. By listing the variables and their
impacts it becomes apparent what key players have a say in the trends in which RPS’s are adopted, and
these are explained as followed. The first independent variable that Chandler assesses is population
growth rate, which is actually behind 1 year because of the information available to policy makers when
drafting legislation. Per capita disposable income is a variable used in order to measure income of U.S.
states, which is also behind 1 year, and measured in hundred thousands of dollars in order to accurately
align with the percentages of the other variables. The non-attainment variable refers to the percentage of
population living in an area considered to have worse air quality than what the National Ambient Air
Quality Standards define as safe. The variable of renewable potential consists of the amount of solar and
wind potential in proportion to total electricity sales. Electricity intense industry variable indicates the
percent of gross state product coming from electricity intense industries and is basically used to
calculate the dependence of a state’s economy on electrical consumption. On the other hand of raw data
are more societal implications, like the variable of government ideology, which indicates where the
state’s political stance and social opinions reside. Ideological distance is a very interesting variable
because it examines the adoption rate in which states take on standards depending on what their
neighboring state has done or plans to do. Once the variables are listed, a logistic regression model is
outlined and visualized through text but mostly charts. This brings about the statistical side of my
research question and introduces mathematics into its answer. When projecting outcomes, in this case
the trends of these standards, it is always an important approach to take because of how data can be
assigned numbers and crunched through algorithms in a more objective manner. The results show that
regional and neighbor diffusion variables are significant in RPS adoption decisions—even when
accounting for ideological distance from previous adopters. While Chandler breaks down RPS trends to
numbers and regression and pinpoints some significant players, statistics always have some limitations.
In this study, the adoption predictions were not consistently lined up with the adoptions that have
already happened. Furthermore, while a variable may not prove usefulness in this study in particular, it
cannot be completely excluded. For example, in the regression, the non-attainment variable did not
express significance, but in the broader RPS picture, air quality is definitely going to factor into whether
a state had a need for more renewables (Chandler, 2009).
Impacts Yin Haitao, assignment professor at Antai College of Economics and Management, accumulates
research on existing empirical data on RPS impact. In his journal he exclaims how studies previous his
own have used cross-sectional approaches that over-simplify RPS impacts and overlook diverging
designs for different states. This study seeks to measure RPS impact in a way that accounts much for
specific RPS design features and how those affect its strengths (Haitao, 2009). Energy Policy Journal’s
Andy Kydes also analyzes RPS impact on electricity but also on fossil fuel usage. Kydes exclaims that
RPS policy reduces the construction of gas and coal generation technologies that would have been built
otherwise. Therefore, in 2020 the RPS initiative is projected to cancel around 96 GW of less coal units
and create 166 GW of more renewable units (99 GW of that being wind capacity) (Kydes, 2006).
Social Implications Chelsea Schelly, whose findings are also featured in Science Direct’s Energy Policy Journal,
reports on the sociological impacts of renewable portfolio standards. She does this by narrowing in on
the residential sector of energy usage and how renewables can integrate into daily household practices.
Before even getting into RPS’s, she more broadly examines how values influence the choices that
people make. This is an important distinction to make because depending on one’s environmental,
economic, conservational, etc. values, his or her take on RPS are going be affected. This is largely why
no two state RPS policies are exactly the same in types of design including types of energy and year
goal must be reached by. Schelly investigates how Colorado’s RPS (requiring 30% renewables by 2020)
was instigated by a ballot initiative that was desired by its own voters and speaks towards values of
Colorado residents. She pinpoints a specific energy source and situation to explain societal implications
of these standards. Her study investigates the interviews done amongst homeowners who have installed
residential solar electric technology in Colorado. The majority of residents interviewed happened to
retired or close to retirement. The social explanation for this is that they may have had much more time
to accrue the savings for the upfront cost of solar panels and they plan on staying put in their current
residence for some time. This is just a specific example amongst many studies that aim to pinpoint
sociological reasoning behind renewable adoptions after Colorado has embraced its latest RPS. The
major goal of this piece of literature was to understand residential motivations and experiences with
renewables (Schelly, 2014).
Costs SciTech Connect journal composed by Ryan Wiser is a comprehensive review of the existing
costs of renewable portfolio standards along with the methods in which he calculates these cost
estimates. Strictly from an economic and statistical perspective, his analysis is based on the incremental
cost of RPS targets. Renewable portfolio standard compliance costs are compared against renewable
energy certificates. This data is accumulated via cost estimates reported by utilities and regulators and
translated into common metrics for balanced units across the board. From 2010 to 2012, average RPS
compliance costs were equal to 0.9% of retail electricity rates when calculated as a weighted-average.
More recently, costs have transitioned to 2% of average retail rates for most states. Wiser discloses that
the comparisons across states are imperfect due to the varying methods and assumptions used in the
specific standards. The use of REC prices to compute RPS compliance costs in restructured markets are
limited in some cases by a lack of REC price transparency and incomplete data on long-term contracts
(Wiser, 2014). Trent Berry, also with the Energy Policy Journal of Science Direct, discusses why
renewable costs are the way that they are. His exclaims that although renewables involve newer, more
expensive technologies, the government puts forth several mechanisms such as grants, loans, indirect
support, and the renewable portfolio standard. Berry utilizes surveys from across the world to
investigate RPS cost effectiveness. Narrowing in on the United States, RPS costs face risks of driving up
electricity prices when the targets are set too high. But in order to minimize this risk, cost caps have
been implemented for renewables. Through his findings and surveys, Berry suggests the cost cap. If
electricity providers are using REC’s, then program administrators can set an unlimited amount of
REC’s that is equal to the price cap. Berry acknowledges that RPS costs are a significant concern across
the country, and his studies aim to find solutions to these worrisome costs (Berry, 2000). Lord Bird’s
research from the Energy Policy Journal of Science Direct inspects the National Renewable Energy
Lab’s Regional Energy Deployment System (ReEDS) model that examines the least-cost expansion of
electricity generation capacity and transmission in the United States. This model examines prices and
emissions caps / carbon emissions with RPS individually and combined. By comparing RPS and carbon
cap scenarios, the effect of varying level caps are observed while the RPS remains constant. On the
other hand, Bird evaluates varying RPS costs while the carbon cap is held steady. Her findings from
these processes divulge that, specifically with costs, that RPS’s do not result in substantial electricity
price increase. Though there is greater technology investment, fuel costs are reduced and offset the
impact on average power prices (Bird, 2011). Cliff Chen with the Renewable and Sustainable Energy
Reviews Journal on Science Direct considers the cost-impact analysis of the RPS’s implemented since
1998. Similarly to previous cost findings being reviewed, Chen confirms that 70% of state costs studies
in the U.S. have electricity rate increase no greater than 1% when RPS is involved. Chen accumulates
this data via models containing RPS policies of 20 U.S. states and the key findings are highlighted in
project costs and input assumptions (Chen, 2008). Gabriella Stockmayar and her journal within Science
Direct’s Energy Policy studies are a bit more unbiased with her RPS cost analyses. Her paper describes
the ways states try to control their RPS costs and while the strengths are included she does not shy away
from the weaknesses they pose. She discloses that implementing RPS’s will never come free and while
utilities and regulators are trying to mitigate costs, one preferred cost limitation approach will never
work in all state cases. Stockmayar’s survey work suggests that the most important factors in curtailing
costs are clarity, consistency, and above all, transparency for customers (Stockmayar, 2011).
Benefits Whereas Wiser examined costs literally based on pricing and economics, with benefits he
expands his strategy and observes the broader social benefits beyond any direct cost savings that may
accrue to utilities. The potential benefits of RPS policies that he scrutinizes include reduced emissions,
water savings, fuel diversity, electricity price stability, and economic development. While many times
U.S. states have attempted to quantitatively assess these benefits, in other cases state legislatures or
public utility commissions require these assessments as part of integrated resource plans (IRP’s) in
preparation for regulatory commissions, energy boards, or public benefit corporations. Wiser’s study
acknowledges how benefits of RPS’s are actually necessary components that states need to know about,
which makes perfect sense. For Wiser’s findings I narrow in specifically on his qualification of
emissions and human health benefits. He uses model approaches to assess scenarios of air quality with
and without renewable energy for comparisons. He also estimates the dollar values associated with
emission reductions in order to monetarily compare them into the economic sector. Specifically, these
emission benefits are estimated into net incremental costs, which when calculated out, range from tens
to hundreds of millions of dollars in savings annually (Wiser, 2014). Chuck Kutscher of the National
Renewable Energy Lab delves specifically into the RPS impacts in Colorado. His study aims to assess
the renewable and carbon impacts currently in place and what has happened since Colorado’s RPS was
increased from 20% to 30%. This is all done through a user input-drive Microsoft Excel model with
assessments of technology, electrical outputs, and carbon reduction for both 20% and 30%. Kutscher
finds that the 30% RPS succeeds in meeting the carbon restrictions necessary to avoid climate change’s
worst impacts, meaning Colorado’s RPS increase has posed environmental benefit. What is most
interesting about this study is that when the author was accumulating this data, Colorado had not
actually increased its RPS to 30% yet, so for Kutscher these conclusions were only hypothetical at the
time (Kutscher, 2007). Though dealing with costs, A. Mahone’s studies in the Energy Policy journal
suggest investment in cost-effect energy efficiency that RPS’s bring about. Using California as a case
study, Mahone demonstrates how RPS benefits can be especially reaped if resource allocation is
improved through energy efficiency (Mahone, 2008). Simone Epsey from the Energy Policy Journal
discusses the main support mechanisms for RPS due to the fact that open market conditions and price
regulation mechanisms favor renewable energies. She analyzes how creating a demand side for
renewable energy first instead of the supply side is a spreading tool. While RPS’s focus on the demand
side, Epsey studies how the higher competition among generators along with the RPS will allow more
freedom of choice on the supply end for meeting requirements (Epsey, 2000).
Differing Opinions RPS vs. Alternatives Scott Hempling and his journal published by the National Renewable Energy Lab define and
analyze feed-in tariffs (FIT’s), an infamous alternative to the RPS. These tariffs obligate retail utilities to
purchase electricity from renewable generators with very specific guidelines. These create a continuing
obligation in the local utility to buy output from renewable producers at standardized rates associated
with generation costs and certain terms and conditions. FIT’s differ from RPS in that they make use of
long-term agreements. Beyond explanation of the alternative, Hempling raises the constraints placed on
FIT’s due to policies in U.S. history. Interestingly, there are features within the designs of the Public
Utility Regulatory Policies Act (PURPA) of 1978 and the Federal Power Act of (FPA) of 1935 that
constrain the transaction of wholesale sale of electricity from renewable generator to retail utility. This
study then prompts Hempling to seek ways in which states can free themselves of these constraints and
put these tariffs to use (Hempling, 2010).
In Science Direct’s Renewable Energy Policy journal, Peng Sun compares his research on two
regulatory policies. This literature review as a whole focuses on renewable portfolio standards, and Sun
examines RPS’s with the alternative policy of feed-in tariffs. Through a two-stage model, Sun compares
RPS to feed-in tariffs by setting up a scenario in which a monopolization firm has a productivity level
and the associated amount of energy required. Then, in one consequence RPS effects are added and in
another consequence FIT effects are incorporated. What Sun finds through this model is that FIT’s are
more efficient than RPS when increasing the quantity of installed capacity of renewable energy and
stimulating productivity to reduce costs. However, RPS prove to be more efficient when reducing
carbon emissions and improving consumer surplus. Sun chooses to neglect social welfare impacts of
each regulatory policy due to the fact that it depends a lot on negative externalities; a topic this research
does not quite delve into as much (Sun, 2014).
Abolhosseini also acknowledges alternatives employed by governments in order to finance
renewable energy development programs. His research supports promising policies that require
renewable energy in investment of small-scale energy production systems. His studies also find that
FIT’s are desirable in certain circumstances, like renewable energy investments that want low-risk,
whereas RPS’s are more appropriate regarding government employed market policies. Additionally
Abolhosseini considers tax incentives in order to adopt carbon emission taxes or emission trading
mechanisms in order to mitigate emissions at lower costs but somewhat indirectly make renewables
more appealing in that way. This study in particular, though it does not crunch so many numbers as
other studies, still considers technological progress, cost reduction, and financial input (Abolhosseini,
2014).
Jared Moore from Science Direct’s Energy Procedia Journal takes a look into low carbon
capacity standards (LCCS’s) as an alternative to RPS for lowering electricity carbon emissions. LCCS’s
create requirements for load-serving entities to move onto new low carbon capacity and provide greater
balance of energy than a RPS, according to Moore. Though cost of new entry estimates, Moore’s
research suggests that with LCCS’s coal fired power plants utilizing carbon capture and sequestration
would have the lowest cost per MW of all low carbon technologies. Moore’s studies come with bias
against RPS and take a route that does not necessarily consider renewables, if the costs are lower for
carbon capture and sequestration as an environmental method (Moore, 2014).
Question of Further Research It is no question that the United States is entering a critical phase of renewable-energy
policymaking. Currently Congress is debating national renewable-energy policy, which leads me to my
question that requires further research. Brent Haddad and his journal continues the dialogue on
alternative approaches to ensuring that public benefits from renewable-resource electricity but
throughout the entire country. In this article, he argues that there are valid reasons for federal
government intervention because of the benefits renewable resources provide to society that are not
captured by the price of electricity. These benefits; greenhouse-gas mitigation, society-wide price-
stability benefits, and long-run national energy-independence should be enjoyed by every inhabitant of
the United States (Haddad, 1999). The Energy Policy Journal also hosts Karen Palmer’s research on the
federal debate of RPS’s. She also suggests cap-and-trade and tax credits on a federal level, suggesting
that RPS’s will have competition as an environmental policy across the country. She specifically
analyzes the Haiku electricity market model to evaluate the economic, technological, environmental,
and cost-effectiveness of RPS’s and its alternatives on a federal level. While RPS’s world substantially
use renewables across the nation, Palmer finds that cap-and-trade programs (CTP’s) are much more
successful in reducing carbon emissions because it distinguishes coal and natural gas electricity, making
it most cost-effective. The point of Palmer’s research in this review is that RPS may not be as feasible as
other policies on a federal level (Palmer, 2005). There are many political figures across the country that
push for federal RPS’s. Thomas Udall, senator from New Mexico, is on congressional record for
amendment of the Public Utility Regulatory Policies Act of 1978 in order to prescribe guidelines for a
federal renewable portfolio standard from 2008 to 2037. Though these attempts were made back in
2005, Udall puts forth some major arguments including graduated annual percentages of supplier base
amounts, encourages federal, municipal, and rural utilities and cooperatives to participate in the RPS
program, and to establish a state renewable energy account program. It is the content and incentives
behind Udall’s encouragement that matters for future questions of federal RPS (Udall, 2005).
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