HomeMy WebLinkAboutStaff Report 1357City of Palo Alto (ID # 1357)
City Council Informational Report
Report Type: Informational Report Meeting Date: 2/7/2011
February 07, 2011 Page 1 of 2
(ID # 1357)
Title: Information Report on Local Generation
Subject: Local Gas-Fired Generation: Review of Past Efforts and Overview of
Future LEAP Implementation Analysis
From: City Manager
Lead Department: Utilities
Recommendation
This is an informational report and no Council action is required.
Executive Summary
This report is provided as background on past City consideration of large, locally sited, natural
gas fired generation as an electric supply strategy. An upcoming analysis to be done as part of
the Long-term Electric Acquisition Plan will re-evaluate this supply strategy.
Background
During development of the Long-term Electric Acquisition Plan (LEAP) the Utilities Advisory
Commission (UAC) expressed interest in receiving some background information on past
analysis of siting a power plant in Palo Alto. The attached report (Attachment A) contains a
history of past efforts, a discussion of the benefits of a locally-sited power plant, and a review
of the risks and obstacles associated with local generation.
Discussion
The attached report is provided as background in anticipation of an upcoming high-level
analysis of local generation as an electric supply strategy. Staff will do this analysis as part of
LEAP. The upcoming analysis is intended to update the qualitative and quantitative
assumptions and observations used previously that led to a 2006 decision to exclude locally-
sited generation from the City’s electric supply strategy. Based on this analysis staff will
recommend whether to reconsider large gas-fired generation in Palo Alto as a long term electric
supply strategy.
Resource Impact
There is no direct resource impact as a result of this report, but the analysis mentioned above
will require staff time and may include up to $25,000 of consulting resources. Funds for such
studies are included within existing budget resources.
February 07, 2011 Page 2 of 2
(ID # 1357)
Policy Implications
This report fulfills LEAP Implementation Task 15, “provide an update of past local generation
feasibility studies and actions to the UAC and the City Council.”
Environmental Review
California Environmental Quality Act (CEQA) review of this informational report on local gas-
fired generation is not required, since the submission of this report does not meet the
definition of a “project” under Public Resources Code Section 21065.
ATTACHMENTS:
Attachment A: December 1, 2010 report to the UAC on local generation (PDF)
Prepared By:Jon Abendschein, Resource Planner
Department Head:Valerie Fong, Director
City Manager Approval: James Keene, City Manager
MEMORANDUM
TO: UTILITIES ADVISORY COMMISSION
FROM: UTILITIES DEPARTMENT
DATE: DECEMBER 1, 2010
SUBJECT: Local Gas-Fired Generation: Review of Past Efforts and Overview of Future
LEAP Implementation Analysis
This report is informational and no action is necessary.
BACKGROUND
In November 2001 the City Council approved the first Long-term Electric Acquisition Plan (LEAP)
in anticipation of the large reduction of electrical energy supply under the City’s newly negotiated
Western Base Resource contract anticipated to start in January 2005. The LEAP included an
exploration of alternative ways of filling in the energy shortfall, including an exploration of the
potential and feasibility of siting a 25 to 50 MW power plant in Palo Alto. Staff studied various sites
from 2001 to 2006. In 2006, as part of an update to the LEAP Implementation Plan, staff
recommended and the City Council approved a revised local generation strategy that did not include
large, gas-fired generation (CMR:169:06).
Current LEAP Objectives and Guidelines related to local generation reflect that decision. They
emphasize small-scale, local, ultra-clean, distributed generation and renewable resources but do not
include local natural gas fired large central station generation as a strategy. As part of the proposed
updated LEAP Objectives and Strategies staff will reassess this approach. Over the next several
months staff will re-evaluate the potential and feasibility of siting large scale gas fired generation in
or near Palo Alto.
This report fulfills proposed LEAP Implementation Plan task fifteen, which is to provide an update
of past local generation feasibility studies and actions. A future report will provide the results of
staff’s updated analysis fulfilling LEAP Implementation Plan task seventeen.
DISCUSSION
A central station power plant typically refers to a power plant built to serve a significant percentage
of a region’s load. It is often contrasted with distributed generation, which typically serves a single
customer’s load, or a portion of it, and is located at the customer site. Central station plants are
typically larger, less costly per unit of energy, and more efficient.
A central station, gas fired power plant located in Palo Alto has some advantages when compared to
other procurement strategies. It can help the utility avoid transmission-related costs, meets Palo
Alto’s local capacity requirements, and may provide some reliability benefits. Investment in a local
power plant also takes advantage of the City’s relatively low cost of capital and may have long term
strategic value to the electric utility. These and other potential benefits prompted staff to spend
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several years, from 2001 to 2006, to further investigate the benefits and identify the costs and
potential obstacles to siting a power plant in Palo Alto.
History of Local Generation Studies
The following is a summary of efforts to site local central station generation starting in 2001. The
history primarily focuses on past analysis of City-owned generation in Palo Alto, but it also
discusses staff analysis of other local and regional generation options, including distributed
generation. The goal is to put past City decisions in context and provide a deeper understanding of
the reasoning behind them.
2001-2003: Local Power Plant Studies
The City’s power plant studies began in 2001 with the City participation in an effort led by Northern
California Power Agency (NCPA) to identify a site for a jointly owned highly efficient gas-fired
power plant (a “combined-cycle” power plant). The study (Attachments A and B) considered a site
in Palo Alto adjacent to the Regional Water Quality Control Plant as well as sites in other NCPA
member cities. A site in Lodi was chosen for further study and eventually became the site of the
natural gas-fired Lodi Energy Center combined-cycle combustion turbine, currently under
construction. The City participated in early feasibility studies of the site but ultimately chose not to
participate as a project owner.
Simultaneously with this study the City began discussions with large customers about hosting
cogeneration plants on their sites. These would be gas-fired power plants where waste heat from
combustion was used in heating loads on customer sites. In 2002 the City completed a preliminary
analysis of the Roche Biosciences site. Although progress was made over the following years no
final project plans were ever developed. Discussions with Roche and other customers continued
through 2008 until Roche, after merging with Genentech, decided to move its Palo Alto operations
to South San Francisco. City staff continues to maintain relationships with customers who have heat
loads suitable for cogeneration.
Staff also investigated power plants outside of Palo Alto but in the Bay Area. In 2003 NCPA issued
a request for proposals on behalf of Bay Area members for purchase of power plants or shares of
power plants within the Bay Area. Seventeen proposals were received, but the City did not
immediately act on any of them. The City instead opted to continue investigation of local generation
within Palo Alto. By 2003 several sites had been identified for consideration. The sites that
appeared to have the most potential were Municipal Services Center and the Los Altos Treatment
Plant sites.
2004-2006: Local Generation Capital Improvement Project
With potential sites identified staff began preparing for more detailed studies. In early 2004 Utilities
Department staff obtained funding for a feasibility study. The study was meant to take place in two
phases. Phase I would involve assembling a multi-disciplinary internal staff team to study issues
associated with power plant siting. It would include a series of public outreach meetings.
Depending on the results of Phase I, Phase II would involve a more detailed analysis of a single site.
On May 10, 2004 the City Council approved this plan (CMR 247:04) with the stipulation that
dedicated parkland should not be used for power generation.
Page 2 of 7
Upon approval of the plan staff assembled a core working group with members from the Utilities
Resource Management Division and the Planning Department. The working group could call on an
extended advisory group comprised of City staff with experience in electric and gas distribution,
water, wastewater, environmental compliance, public communications, law, finance, and risk
management. This team proceeded to evaluate several power supply alternatives including a
combined-cycle gas plant on one of several possible City-owned sites, renewable local distributed
generation, a power plant on a local site outside Palo Alto, and customer-sited cogeneration.
During 2004 and 2005 the working groups reviewed various local sites to identify obstacles to
building a power plant. The group discovered that even a modest generation plant would be
challenging to build in Palo Alto. Aside from the technical concerns unique to each site, none of the
sites had land use characteristics that could be characterized as primarily industrial, making them
inhospitable to an industrial use with the impacts of a power plant. The economics were also
slightly unfavorable, meaning that a power plant might not reduce power costs even if it was a viable
strategy to reduce price uncertainty.
Other efforts during this time included investigation of cogeneration and distributed generation
opportunities. Staff worked with the Rocky Mountain Institute and consultant Energy and
Environmental Economics (E3) to study the economics of such projects and other alternatives such
as energy efficiency.
2006 to Today: Focus on Renewables and Combined Heat and Power
Due to the siting issues and the potential for public opposition to any of the proposed sites, staff
recommended that the City focus on renewable distributed generation, renewable power, preferably
in the Bay Area, and customer-sited cogeneration. A recommendation was included as part of the
LEAP Implementation Plan update approved by Council on April 17, 2006 (CMR 169:06) to not
proceed with Phase II of the Local Generation CIP. Instead staff recommended focusing on
customer-sited cogeneration as well as renewable power plants outside of Palo Alto but in the Bay
Area. The City Council approved the staff recommendation.
Over the next several years procurement efforts were primarily focused on renewable generation.
Several resources were obtained, some of which were in the Bay Area. Staff continued to pursue
cogeneration opportunities (5-10 MW) on large customer sites as well as some conventional
generation proposals in the Bay Area. In the course of pursuing these goals the City created the
PLUG-In program, an incentive program for customer-sited distributed generation for mid-sized and
large customers.
Future Local Generation Studies and Efforts
The proposed LEAP strategy related to local generation calls for a re-evaluation of large scale (25-
50 MW) gas fired generation located in or near Palo Alto. This effort will involve updating costs,
values, and other assumptions from previous analyses and comparing the costs and benefits of these
strategies to other strategies such as entering into forward contracts or purchasing renewable energy
to meet the goals set in the City’s Renewable Portfolio Standard and reduce greenhouse gas
emissions.
Below is a discussion of some of the potential costs and benefits to locating a 25-50 MW plant in
Palo Alto. It expands on previous discussions of local generation in the September 1, 2010 and
Page 3 of 7
November 3, 2010 UAC reports on LEAP. Those reports discussed both distributed and central
station local generation strategies, but the cost and benefit discussion below is only meant to address
a central station strategy.
Potential Costs and Benefits of Central Station Local Generation
There are two types of benefits associated with local generation: capacity- and energy-related
benefits. Capacity-related benefits are realized even when the generator is not running while
energy-related benefits only accrue when the generator runs.
The primary capacity-related benefits of local generation are reliability and the ability to fulfill local
capacity requirements imposed by the California Independent System Operator (CAISO), the entity
that operates the California transmission grid. The value of reliability depends on the economic cost
to customers of losing power, the likelihood of an outage, and the extent to which customers already
rely on backup generators. The reliability of the plant is also a factor. In an earthquake, for
example, a local plant or its gas supply might be damaged, making the plant unavailable.
When considering reliability, local generation must also be compared against the strategy of building
additional transmission lines. Adding a second point of transmission interconnection provides an
additional path for electricity in the event of a catastrophic failure like the one which occurred on
February 17, 2010, and so reduces the reliability value of local generation. An additional
transmission line could also be capable of serving the entire city, whereas a small local generator
would only be able to serve a portion of Palo Alto’s load. For example, in a previous study a 25
MW plant was enough to serve the downtown area while a 50 MW plant could serve the Stanford
Research Park.
The local capacity requirement imposed by the CAISO is based on the fact that the Bay Area and
other PG&E area load pockets are constrained in the amount of transmission entering the load
pockets. Utilities serving loads in the Bay Area are required to own or contract for a minimum
amount of generation capacity in the designated local load pockets. The City can fulfill this
requirement through local generation but could also fulfill it in other ways, such as by contracting
for capacity elsewhere in the Bay Area. The City’s annual cost of purchasing this local capacity at
present is estimated to be approximately 75% lower than the cost of building a central station
generation.
In addition to the capacity benefits listed above, there are energy-related benefits to local generation.
The first is the benefit of a locally-owned plant as a way to offset part of the electric portfolio’s
exposure to market power prices. A combined-cycle gas power plant would provide some
diversification from market-based electricity purchases. This benefit is not unique to local
generation and could also be realized by contracting with or becoming a joint owner of gas-fired
generation outside of Palo Alto. In fact, a power plant outside of Palo Alto could have some
advantages over a local plant as it would be more likely to achieve economies of scale. Large power
plants tend to be more efficient and economic, but it would be difficult to site anything larger than
25-50 MW in Palo Alto. A larger plant like the Lodi Energy Center (250 MW), for example,
requires at least 4.4 acres of space with facilities 30-40 feet tall and a 150 foot exhaust stack. With
any gas-fired plant, though, whether it is local or non-local, the benefit of the plant as a way to
manage power price variability is somewhat limited. This is because power prices in California are
Page 4 of 7
roughly correlated with gas prices, meaning that the cost of running the plant will tend to rise and
fall with the market.
The other energy-related benefit that a local plant can realize is avoided transmission costs. With a
local plant in operation Palo Alto would be able to avoid some types of transmission charges. The
value of this is somewhat uncertain. Under current CAISO rules some of these charges can be offset
by local generation. Though there are no current plans to change these rules, it is possible that a
future regulatory regime could result in this right being rescinded. This would mean that any local
plant built to realize these benefits would lose a degree of value. Other projects could also reduce
this benefit. For example, in the past City staff has evaluated upgrading the transmission lines
serving Palo Alto to operate at a higher voltage, a project that would reduce the value of avoided
transmission charges.
Table 1: Summary of Local Generation Benefits
Benefit Description Alternatives
Capacity-related benefits
Reliability Protection against outages Have customers rely on backup generators
Build a new transmission line to have a
second point of interconnection.
Capacity cost The City is required by the
CAISO to own or contract for
capacity located in the Greater
Bay Area (GBA) load pocket
Own or contract with power plants outside of
Palo Alto but within the PG&E load pockets
to meet the regulatory requirement.
Energy-related benefits
Energy costs Diversify fuel supply, reduce
future price uncertainty
Forward market purchases
Own or contract with power plants outside of
Palo Alto for energy.
Transmission
costs
Losses, high voltage wheeling
charge, low voltage wheeling
charge
Upgrade the transmission interconnection
voltage from 115 kV to 230 kV to partially
avoid low voltage wheeling charges
Table 1 summarizes some of the benefits of local generation discussed above and identifies
alternatives for capturing the benefits. There are uncertainties associated with each of these benefits.
For example, if the price of gas is unfavorable or electricity prices drop due to advances in
generation technology, the value of the plant could drop. Regulations related to transmission or
local capacity could change, and construction of more transmission or generation infrastructure in
the Bay Area by other utilities could reduce the value of Palo Alto’s local plant as well. Owning a
generating plant would also expose the City to additional North American Electric Reliability
Corporation (NERC) and the Western Electricity Coordinating Council (WECC) regulatory
requirements, which require costly compliance measures. These uncertainties will be considered in
the analysis of a local gas-fired generation that staff intents to complete. Additionally, the analysis
will consider the effect that a local plant would have on the composition of the City’s portfolio.
Figure 1 shows the City’s portfolio in 2015 with a 25 MW gas-fired generation contract, assuming
33% renewables and an average hydro year. This chart assumes that the plant is efficient enough to
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run throughout the year, but it is possible that the cost of the gas to run the plant will exceed the
price of power in the winter. This is a potential disadvantage to this strategy, since winter is the time
when the City’s portfolio is most exposed to market prices.
Figure 1: Electric Portfolio in 2015 with 25 MW Local Generation
Next Steps
Staff will return to the Utilities Advisory Commission in June 2011 with a detailed analysis of the
gas-fired 25-50 MW local generator strategy. This will involve an update to the costs and benefits of
the strategy based on current power prices, gas prices, carbon emissions costs, power plant costs,
and value of enhanced reliability benefits and will consider the uncertainty around the value of large
scale local generation. The analysis will also include a qualitative update of siting issues for two
local sites, the Municipal Service Center and the Los Altos Treatment Plant sites.
RESOURCE IMPACT
This evaluation will require staff time and may include up to $25,000 of consulting resources. Funds
for such studies are included within existing budget resources. While the evaluation has limited
impacts, a future decision to implement a local generation strategy would involve impacts on City
resources.
POLICY IMPLICATIONS
This update fulfills proposed LEAP Implementation Plan task 15, “Provide an update of past local
generation feasibility studies and actions to the UAC and Council.” It is consistent with other
proposed LEAP Objectives, Strategies and Implementation Plan tasks and is in support of the
Utilities Strategic Plan approved by the City Council.
ENVIRONMENTAL REVIEW
California Environmental Quality Act (CEQA) review of this informational report on local gas-fired
generation is not required, since the submission of this report does not meet the definition of a
“project” under Public Resources Code Section 21065.
Page 6 of 7
ATTACHMENTS
Attachment A: Executive Summary from 2001 NCPA Power Plant Siting Report (pp 1-10)
Attachment B: Palo Alto Siting Study from 2001 NCPA Power Plant Siting Report (pp 30-39)
PREPARED BY: JON ABENDSCHEIN, Resource Planner jt''-' ,
SHIV A SWAMINATHAN, Senior Resource Planner ~y
MONICA PADILLA, Senior Resource Planner
REVIEWED BY:
Page 7 of7
PBPowsr
Executive Summary
Background
Potential Cycles
• 80MW
• 50MW
• Heat & Mass Balances
• Project Cost Summary
Potential Sites:
1 Nov. JOOl
TABLE OF CONTENTS
Alameda UC Davis
• General
• Site Evaluation matrix
• General Araa Map
• Biological Listing
• Biological Resources Map
• Site Images
Roseville
• General
• Site Evaluation Matrix
• General Araa Map
• Biological Listing
• Biological Resources Map
• Site Images
Palo Alto
• General
,. Site Evaluation Matrix
• General Araa Map
• Biological Listing
• Biological Resources Map
• Site Images
Emission Considerations
• Basic Model
• Annual Emissions
• Offset Costs
Attachments:
•
•
•
•
•
•
Lodl
•
•
•
•
•
•
Attachmenl1: Oclcber 2, 2001 Siting Study Presentation
-1-
General
Site Evaluation Matrix
General Araa Map
Biological Listing
BIological Resources Map
Site Images
Site Evaluation Matrix
Gen,eral Area Map
Biological Listing
BiologIcal Resources Map
Site Images
PB PtJWBr, Inc.
WZI/nc. EXECUTIVE SUMMARY
EXECUTIVE SUMMARY
PB Power and WZI Inc., its environmental/permitting consultant, were selected by the
Northern California Power Agency (NCPA) to undertake a study to evaluate the potential for
developing new power generating plants at selected sites of various NCPA members (in
addition, UC Davis was evaluated as a potential site). Each site was visited by a team
conSisting of staff from NCPA, PB Power, and WZllncand was evaluated wnh regard to the
issues surrounding the potential siting of a power plant including technical considerations
such as interconnection with a high pressure gas supply and with HV transmission facilities,
environmental considerations such a noise, emission impact area, and area biology, and
local history with such projects.
For this study the following sites were visited: Alameda, Roseville, Palo Alto, U .C. Davis, and
Ladi. At each site the team met with local staff that shared information relative to the site and
the issues surrounding siting a power generating facility, After the sites had been visited a
meeting was held with NCPA staff and site representatives, There was general discussion
that the forecasts for the California power market had changed dramatically over the
summer. A re-evaluation of the members' power requirements as well as understanding the
issues surrounding permitting plants in California over 100 MW led to a decision to deviate
from the original plant size of 125 MW. It was established that the final evaluation of the
sites should be made relative the siting of an 80 MW power plant at Roseville, UC Davis, and
Lodi and the siting of a 50 MW power plant at Alameda and Palo Alto.
As part of the siting study an EPC budget cost was developed for an 80 MW and a:-SO MW
facility utilizing Thermoflo's PEACE program. The EPC cost for an 80 MW plant was
estimated to be $60,36 million and for a 50 MW was estimated to be $44,83 million., This
equates to a cost of $736.5/kW for an 80 MW facility and a cost of $912.4 / kW for a 50 MW
facility, In addition to the above costs the offset costs were estimated to be $1,04 million for
a 50 MW facility at Palo Alto and Alameda, $1,03 million for Ladi, $1,58 million for Roseville,
and $264 thousand for UC Davis,
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• Alameda Site
This site is well situated to take advantage of proximity to the NCPA CT1 (an
unmanned facility), local HV transmission system, reClaimed raw water from
EBMUD, a supportive city administration, reasonable access to high pressure
natural gas (exact pressure and availability being confirmed), and bounding future
commercial development area, There are several significant issues which
although not fatal require being addressed in the very early stages of any project
development. First, the potential site is not currently owned by the city. Second,
there is the potential for soil contamination on the prospective site as well as a
potential construction parking / laydown area. Third, due to the proximity of
housing and adjoining park, noise generated by facility will need to be addressed
both with respect to ordinance requirements and to the design required to meet
the ordinances. Due to the parcel size and shape a 50 MW facility would be best
suited for development.
- 1 -
PB Pow"" Ine:" WZI IlJc~ EXECUTIVE SUMMARY
"""
• Roseville Site
This site is located away from current residential development on a large parcel of
land owned by the City of Roseville and adjacent to a proposed Enron project
(Roseville Energy Facility). There is reasonable access to high-pressure natural
gas and HV transmission facilities and the potential for a sharing of costs should
both projects go fOlWard. A major consideration at this site is the availability of
water as the Enron project has rights to the wastewater available from the
adjoining PGWWTP (Pleasant Grove Waste Water Treatment Plant) for the next
several years, Currently within California it is very difficult to be permitted for the
use of non-reclaimed water for power plants and to date no other source of water
has been identified.
• Palo Alto Site
This site is situated on landfill adjoining the Palo Alto WWTP, High-pressure
natural gas and HV transmission facilities are located within a short distance,
Due to the size of the parcel available and the capabllHles of the existing Palo Alto
switchyard this site would be better suited for a 50 MW plant. In order for this site
to be developed, a citywide election would be required to approve changing the
proposed use of the site from parkland (upon closure of the active landfill) to a
power plant facility. This usage issue would need to be clarified very early in any
development of a power plant at the Palo Alto site.
• U,C. Davis Site
"
There are five potential sites all within the same general area on the UC Davis'
campus south of 1-80 that are suitable for siting an 80 MW power plant. There is a
high-pressure natural gas line adjacent to the sites and a UCD 50 MW 69 kV
switchyard close to all sites. There is adequate wastewater available from the
nearby campus WWTP. The diversion of this discharged waste water from Putah
Creek to a power plant may be a local water use issue. Currently UC Davis is a
PG&E end user and as such cannot become a power supplier without changing
the existing situation in some manner, UCD has also expressed a desire for a
cogeneration facility that would dictate a change from the "basic" 80 MW plant
since there is not adequate steam available from the generating plant to meet the
campus' needs. Depending upon which site was developed and its proximity to 1-
80 some cooling tower plume mitigation may be required.
• Lcdi Site
This site Is well suited for a generating plant being located between the NCPA
CT2 and the Lodi WWTP. HV transmission is available at the existing CT2
switchyard and high-pressure natural gas is available nearby. Wastewater is
available from the Lodi WWTP, Situated between two industrial facilities and
being in an agricultural area there should be no major permitting concerns. This
would be the only sHe where existing staff and infrastructure could be used to
operate and maintain the proposed faCility. Due to the proximity of 1-5 some
mitigation of the cooling tower plume may be required.
-2-
PB Powar, Inc~
t'IIZlllftt,.
Recommendation
EXECUTIVE SUMMARY
All of the sites have the potential to be developed into power generation facilities and none
have "fatal" flaws that would prevent the sites ever being developed.
Recommendations for the individual sites are:
• Lcdi would be the choice to meet the objective of having a power generation
facility on line in the 2004 timeframe. The Lodi site offers available siting adjacent
to an existing NCPA facility, economic benefits due to its location near utility
connections, and the lack of any pertinent siting issues.
An additional potential project enhancement at Lcdi would be the conversion of
the existing LM5000 with heavy STIG to an LM6000 and exporting the steam
produced in the existing HRSG to a new steam turbine at the 80 MW plant.
• Roseville could become a prime candidate for a power plant should the Enron
project fail to be developed and the PGWWTP wastewater become available.
There would be some additional expenses at Roseville with regard to high-
pressure natural gas line and HV transmission lines that are not present at Lodi.
• Alameda is currently evaluating other sites for possible consideration as a power
plant site that hopefully would eliminate the issues of ownership, soil
contamination, and noise in residential areas.
• Palo Alto's site has many positive attributes as a potential site; howeve{, the issue
of requiring voter approval to change the allowable usage from a future park to a
power plant facility remains a significant unknown risk.
• UC Davis has five potentially very developable sites for an 80 MW power plant,
however, the status of UC Davis as a PG&E end user needs to be resolved.
Additionally, the issue of UCD desiring steam from the power plant for Its internal
usage must be addressed as the steam quantities being considered cannot be
supplied by the 'basic 80 MW design' considered in this study.
It is recommended that Lcdi be the first site developed. With respect to the development of
the remaining sites, the obstacles to development as pointed out in this study need to be
resolved.
-3-
PB Power, Inc.
WZllnc.
BACKGROUND
BACKGROUND
PB Power was selected by NCPA to provide services for the Electrical Power Generation
Project. Originally, the initial phase of the services to be performed was to evaluate two sites
for their potential to meet the project objectives of an initial installation of a 125 MW
combined cycle (CC) plant with room for a second 125 MW CC plant. By the time the study
was initiated, the scope had changed to a fatal flaw analysis of five (5) sites with the intention
of reducing the sites to the original two. During the, site visitations it became clear that
although none of the sites exhibited a true "fatal flaw", some had more challenges to the
development of a power generating plant than others. It also became evident that there was
broad interest from all host sites that the NCPA members felt the need to develop power
plants through NCPA and that each member's staff was enthusiastic about the prospect of
building a power plant at their site. (The exception may be Roseville due mainly to the
current discussions between Roseville and Enron regarding the project being developed by
Enron at the Roseville Pleasant Grove WWTP.)
Although the power market in California seems to have stabilized during the last six months,
there remains a great deal of uncertainty regarding the future. As the issues surrounding the
permitting requirements for various size power plants was better understood by the
members, a plant under 100 MW had great appeal and, consequently, a plant size of 80 MW
was selected as the nominal size where the site space would allow.
A team consisting of NCPA, PB Power, and WZI staff visited each site. During these visits
the team reviewed specific aspects associated with siting a power plant and in particular
whether there would be significant permitting or design issues. Each site's local staff
completed an evaluation matrix which served as a compilation of information regarding the
siting and operations for each site. This matrix covered all aspects of siting a power plant.
After receipt of a completed matrix, site visits enabled the team to better appreciate the
specific issues (technical and non-technical) surrounding the siting of each particular power
plant. Additionally, the team met with local staff to review project elements and provide
information regarding the siting issues.
Each site affords its own unique set of opportunities and challenges, and it became evident
that a weighted ranking of the sites would not be a suitable means of presenting the results
of the site visits. It was therefore decided that the results of the visits would be presented for
the member's consideration for locating a power plant with the intent that each site would be
evaluated solely on its own merits.
13572 -4-
PB PDWIH', Inc~
WZllnc,.
POTENTIAL CYCLES
80 MW configuration
POTENTIAL CYCLES
This level of output was selected to be the basis of evaluation for those sites that had no
space or other restrictions. The actual design utilized was a combination of GTPro (a plant
design software program from Thermof)o) and reference to an 80 MW plant being deSigned
by PB Power for Modesto Irrigation District. A facility of this capacity would qualify for the
Small Power Plant Exemption (SPPE) with respect to the permitting requirements of the
CEC. The SPPE licensing process is a much shorter process and, therefore, can be very
desirable.
Facility Characteristics
• Plant gross output at 102°F with full duct firing -81 MW
• Plant gross heat rate: 7707 BTUlkW-hr (LHV)
• Gas turbine -LM6000 Sprint with water injection for NOx control
• Condensing Steam Turbine -40 MW rating
• Deaerating vacuum condenser
-.
• Two pressure HRSG with SCR and CO catalyst and duct burner fired to 1500°F
• Turbine air inlet chiller
• Makeup water @ summer high is -1.0 MGD (700 gpm)
• Maximum fuel consumption @ summer high is 631.1 Million Btuh (LHV) or -694.2
Million Btuh (HHV)
• Budget contractor's cost $60.36 million
• Budget contractor's cost $736.5 I kW
50 MW configuration (Palo Alto and Alameda sites)
This size power plant was selected as being suitable to PalO Alto due to available site
acreage and to interface with existing PalO Alto switch yard capabilities. This size facility
could also fit into the Alameda sHe. A facility rated below 50 MW would not require a state
licensing process and could be a much shorter permitting time that a normal AFC filing with
the CEC.
13572 -5-
PB PDtwN', Im:-.
WZ//nt. POTENTIAL CYCLES
Facility Characteristics
Note:
1.
2.
13572
• Plant gross output at ISO with full duct firing 49.2 MW
• Plant gross heat rate: 7556 BTU/kW-hr (LHV)
• Gas turbine-LM2500+PR with low NOx combustor for NOx control
• Condensing Steam Turbine -20 MW rating'
• Vacuum condenser
• Two pressure HRSG with SCR and CO catalyst and duct burner fired to 1200'F
• Turbine air inlet fogging (or evaporative cooling)
• Makeup water @ summer high is -0.5 MGD (310 gpm)
• Maximum fuel consumption is -371 Million Btuh (LHV) or -408 Million Btuh (HHV)
• Budget contractor's cost $44.83 million
• Budget contractor's cost $912.41 kW
'.
The 50 MW design was not optimized, but rather selected to stay below 50 MW. This
would allow all permitting to be local. Should actual site support larger output, then the
output can be increased by increasing the steam turbine Size.
Costs are budget for comparison only. These are basic EPC numbers and do not
reflect owner's costs nor site speCific costs such as gas supply interconnect, HV
transmission interconnect, etc.
-6-
PB PDwer, Inc.
WZ/Inc.
tf GT MASTER 102.1 file.Y9 Bror.)!; NCPA BaSic BO MW power plant, summer high maximum oulpl.ff.
3 inr.h HgA de5ign b~5i5, 25 ppm NO~
14.65 p '~~·~~~~~~~~~I
1X GE LM6DOOSPT 1056 m 1G? T
2!1%RH
1021.3m
90ft elev. 47323 kW
15.18 P
B57 r
1056M
115T
267.2 M
219T >
---16,99p
219T
2ff7..2M
14.47 P
48T
1019.7 rn
r;I14 19.6 m
lH'J421674 kBTUih
77T
111.1p "'.1p
323T alBT
267.2 M 5.5W M
--,-___ c-==7C ___ -cc-C--~-___ -~-'3=~~~~~~~~~~ ..
~aJ, Tl.Fl, M~L Steam Prup'9(ties: Th-etmoflow· STCl'dlto;:
1357.4p
4!19T
2Bl.2M
426 598
106.9 p '1354,1 P
501T 572T
5.596 M281.2 M
599
39f! 1O-Z'.2001 08':36:34 flle=Z:\N(;PA pu_ plan! sl~·11!1 ~AFC'\Calculatkmsl.BO Design@5ummerhlgh,GTM
NCPA Power Genaratioo Prujecl. ~ California
25 ppm NO;t
1263.9 P
950T
2nUIM
C 0.437 M
1354.1 P
583 T
27BAM
699
Net Power 61906 kW
LHV Huat Rifle 7T07 BTUlkWh
72.3B %N2"Ar
12.71 %02
3.265 %C02fSm
11.&4 %H20
38734 kW
'.472 P
1f5T
283,7 M
~' 854 T
1D56M
"DB.Z ~~~ .,rr
271M M
1245 15aD
.CH4 19.742 M
POTEJIITIAL CYCLES
/lB Power, Inc.
WZlInc.
d' GT~ASTER10,2~~ SleYeBroclo:. >.
14.65 p ~-
59T ...... I ISO%RH
1020.2 fll
!IO It I:lKlV.
NCPA Bas1c:: BO MW puwsr pian!. ISO output without du!:l bUflltlr
:3 it"lCtl HgA. dI:nl:"lQn balii!; (@5UIl'll'J"l;eTmaxj. 25 ppm NOx
lXGE L.,'\t6!lOOSPT 1056.4 m
47:3B4 j(W
15.12 P
BSS T
11)00.4 ~
Net Power 56797 Io:.w
LHV Heat RaID 7421 BTU/Io:.Wh
!.lA6 %N2+Ar
12,74 %02
3.264 %C02+S02
11.53 %H20
20 ppm No...
93T
116.5 M
1VI7p
46T
11J'2O.2 m
~6.ep
7SST
99.39 M
kJ~l ····Itti' ·····t I f(lE++ -------I."1PE21-1I'lr'~~f19PE2H.",,-tim ... HPB, Ltv t . r.)J
322T
1056.4 M of t .---36?'Ap
436 T
l1fl.{JM
629.7 p 91.66 P
491T 322T
116.5 M 17,69 M
475 500 546
PlP$laj, 11F], Mlkpph], Sleam Properties: Thermoftoloft· STQUIK
13-22.1 P
570T
100.4 M
575
59.58 p 1321.6 p
400T 580T
17.69 Ml00A M
.576 "
3gB 10-22v2001 09:34:36 file"'z:\NCPA P'OW9f plant siting ~AI'C',CulcuLations\BO Deslgn@ISOwlthoutDB.GTM
NCPA Power G9I1enrtion Project, Nortl'tsfn (:~Iifornil'l
963.1 P
540T
99.~9 M
563
12Qo'l7IM
0]36 p
92T
117M
=lL~ i 1 853T
1055·.4 M I
5155.1 p <.----~
757T
99.39 M
7\i4 853
POTENTlIU. CYCLES
tf GT P;C 10..2.1 StiNe Srock
"4.5ii p ~.C74
59 -a: % ... H
Bil3n
10ftelw.
99T
141.7 M
172p
200T
147JIVI
C:..j4 ~~~.Mil m
LtiY 271992 ksTUftt
17T
1T.2p ,roT
3.068 M
NCPA power plant tiiting '5wdy
50 MW Pelu Alto alternative
1)', (';;6 l.MZ500 ... PR
pl""'l, 1]1-1, _hi, __ , n.um-.. -smUll(
398 10-22-2001 15.'04:5c! fikFL::'V'1CPAPOW ... O MW PA REFERENCE PLANTW,f'R.GfF
NCPA PO'Ifef Gf1rlelation Ptujed NoMam Calkmlia
691.1 rn
e52,8p
5-22 T
141.1M
800 P
95Q 1
1463M
Net POlt'll!r491aa Io;W
LHV Hom Ri'lb$ ~20 I3TL'lkWh
75.S <:<"N2+.Ar
1.3,501. r.cr2
POTENTIAl. CYCLES
1-Z€9 ':,co:?~so:z
lJ:eihl: ~H20
rCH4
:),17aM
PS Power, InD~
WZllllc.
Project Cost Summary -80 MW Basic Design
I • Reference Cost
I I Specialized Equipment : 32,698,000
: II Other Eaulpment 3,780,000
: III Civil 1,932,000
! IV Mechanical 3,866,000
: V Electrical Assembly & Wiring 360,400
: VI Buildillil s & Structures 577,100
• VII Englneerlng~Plant Startup 3,399,000
Subtotal -Contractor's Intamal Cost 46613000
VIII Contractor's Soft & Miscellaneous I 6,028,000
Costs
Contractor's Price I 52,641,000
IX OWner's Soft & Miscellaneous I 4,738,000
Costs
TataJ-Owner's Cost 57,379,000
•
Nameplate Net Plant Output 81.95
Cost per kW -Contractors 642.3
Cost per kW -Owner's 700.1
Project Cost Summary -50 MW Basic Design
13S12 -10-
POTENTfAL r;YCLEti
I Estimated Cost
I 35 0il8 000 USC
i 4054000 USC
I 2,951000 USC
5,931000 USC
526900 USC
843,200 USC
3,405,000 USC
52779,000 USD
7,581,000 USC
60,361000 USD
5,432,000 USC
65,793,000 USD
i
81.95 .MW
736.5 USD perkW
: 802,8 USD perkW
PB Power, Inc.
WZI Inc.POTENTIAL SITE: PALO ALTO
13572 - 30 -
POTENTIAL SITE
Palo Alto Site
General: The Palo Alto site is located between the existing WWTP and the landfill that is
slated to be converted to a park upon closure of the landfill. Current use of the site is for a
recycling center and a city run urban composting program. Although the particular site is
remote from residences there are nearby commercial offices and Baylands. There is a small
craft municipal airport located roughly 0.5 miles to the west and the flight path is just to the
north of the site. An additional consideration for this site is the requirement that any use
other than park must be approved by a general vote of the Palo Alto residences. Space
between the site and the southeastern boundary of the WWTP must remain for future
expansion of the WWTP.
NCPA Site Evaluation Matrix
Category Summary Comments
Parcel
Size Adequate for 50 MW
Ownership City of Palo Alto
Const. Area Could be tight and require careful consideration
Zoning Need to have city voters approve use for power plant
General Area Adjacent to bayland, WWTP, landfill, and near commercial / office areas
Ambient temp. Bay area, good for gas turbines
Utilities
HV Transmission Available at Palo Alto SWYD ~1 mile across U.S. Highway 101
Natural Gas High pressure available ¼ mile
Raw Water Available for adjacent WWTP
Waste Water Return to WWTP
Emissions
ERCs Available Palo Alto does not own any ERCs.
Nearby receptors Nearest residences approx. 4,000’. Nearby to municipal airport, nature
preserve, and future park.
Environmental
Mitigation req’d Extensive biological resources within area.
Contamination Not probable
Visual Will most likely require some architectural considerations
Noise May require some consideration during design
Other
Community
support
Community support/opposition unknown. If active opposition there could be a
major impact on schedule / viability.
PB Power, Inc.
WZI Inc.POTENTIAL SITE: PALO ALTO
13572 - 31 -
Parcel Details
Size Comments
1 Actual area of site. 3 acres for 50
MW CC. (may be able to squeeze
into 2 plus acres.)
2 Site shape and orientation with
respect to utilities, wind, etc.
A 2 to 3-acre parcel is located between Palo Alto WWTP
and a city landfill, with the current use being city
composting and recycling. The landfill is slated to
become a park upon closure. Due to the proximity of the
future park there may be local pressure to keep site size
to an absolute minimum. Nearby municipal airport (small
craft) may necessitate cooling tower plum suppression
and stack height limitations.
Ownership
1 Clear title to land or option
2 Potential acquisition.
3 Ownership of adjoining property.
Ownership is by City of Palo Alto; however, it appears that
a city vote is required to allow a power plant to be
constructed rather than converting to parkland. Future
location of existing composting and recycling operations
not established if power plant were to be constructed.
Construction parking/laydown area
1 Available as part of site.
2 Potentially available as adjoining
property that leased, etc.
Depending upon the timing of power plant construction,
the area for future WWTP expansion may be available. If
not available, then a portion of the landfill area may be
required on a temporary basis.
Zoning
1 Zoned industrial, commercial, or
residential.
2 Can be rezoned if required.
3 Zoning boundary relative to site.
Zoning is Public, however, there are restrictions on usage.
General Area
1 Commercial, industrial, or residential.
2 Adjoining to residence or
commercial.
3 Economic surrounding.
4 Construction traffic routes and
impacts.
5 Delivery routes of hazardous
materials.
The area is bounded on the southeast by landfill (future
park), on the northwest by the WWTP, and northeast and
southwest by Baylands Nature Preserve. There are
commercial offices to the west across the Baylands
Nature Preserve. U.S. Highway 101 is located to the
southwest beyond the Baylands Nature Preserve.
Ambient Temperature
1 Summer high temperature
2 Annual temperature
3 Power output impact.
The average summer high is in the high 70s while the
annual average temperature is approximately 58 F. With
proper inlet air cooling (evaporation or chillers) the
summer output would not be adversely affected.
Proximity to new IPP project
1 Impact of new power plants on
transmission.
2 Utilization of shared utilities?
3 Precedents set by AFC.
There does not appear to be any significant IPP activity in
the immediate vicinity. There are multiple large IPP
developments throughout the greater San Francisco Bay
area. Each development faces its own set of
considerations/complexities.
PB Power, Inc.
WZI Inc.POTENTIAL SITE: PALO ALTO
13572 - 32 -
Utilities
Transmission Comments
1 HV access and voltage.
2 Location of tie-in relative to local grid.
3 Local system impact.
4 Ownership of grid @ connection.
The Palo Alto 60 kV SWYD, located ~1 mile away, could
accommodate input from a 50 MW power plant with only
minor upgrade. Right-of-way for new transmission line
should not be a problem since it will generally be
adjacent to existing an ROW. Grid impact would only be
a reduction by Palo Alto in its consumption by 50 MW.
How this load reduction would affect the north-south
power transmission would probably be highly dependent
upon whether other IPPs actually get permitted.
Natural Gas
1 Local access.
2 Main and distribution pipeline
ownership.
3 Quantity available without system
wide impact.
4 Pressure available.
5 Pressure available with system
upgrade.
Available at 300 – 400 psig from PG&E main gas located
¼ mile away. Consumption quantity would most likely
not impact line capacity. There may be some impact due
to other IPPs at the north end of the line if they are
permitted.
Raw Water
1 Local availability (& source).
2 Quantity available (time of day
dependent).
3 Quality of water.
4 Available water rights.
Tertiary effluent from the Palo Alto WWTP would be
available for raw water usage. This plant is located
adjacent to the site. Ample capacity is available year
round.
Wastewater
1 Local discharge possibilities.
2 Discharge quantity restrictions.
3 Discharge quality restrictions.
4 Long-term arrangements possibilities.
Plant wastewater may require treatment in order to be
discharged back into the Palo Alto WWTP. This would
be preferable to any discharging into the San Francisco
Bay (which would require a NPDS permit and is not
considered to be a realistic option).
Emissions
ERC availability Comments
1 Actual credits owned by NCPA
member.
2 Potential additional credits from site
NCPA member.
3 Access to ERCs within air district.
4 Cost of ERCs in air district.
Palo Alto does not own any ERCs. The estimated cost to
acquire the ERCs is $1.04M. The close proximity of the
site to the landfill and its elevated area (hill) will effect
emissions dispersion. This, coupled with the possible
stack height restriction, could create a issue that would
be difficult to mitigate.
Nearby receptors
1 Local or downwind
residences/schools, etc.
2 Distant wilderness, recreation, etc.
3 Adjacent property or air and CT drift.
Nearest sensitive receptor (residential) is approximately
4,000’ northwest. The possible site is adjacent to the
Palo Alto Baylands Nature Preserve. The Palo Alto
Municipal Airport is located approximately 2,500’ north.
This will limit the height of any structures within the plant.
Preliminary review indicates a stack height limit of 50’.
PB Power, Inc.
WZI Inc.POTENTIAL SITE: PALO ALTO
13572 - 33 -
Environmental
Mitigation requirements Comments
1 Other than listed below, e.g.
Endangered species, vernal pools,
agricultural streams, etc.
Several endangered animals and an endangered plant,
as well as species of special concern, have been noted
in the general vicinity of the plant site (see map). Other
threatened, endangered, and special concern species
area also noted in the area. A thorough biological
resources study would be required to determine the
exact extent of their habitat. This, coupled with the close
proximity to the Baylands Nature Preserve would make
Biological Resources a key issue.
Contamination
1 Known soil contamination on site.
2 Potential soil contamination on site.
3 Contamination of construction impact
area.
4 Potential water contamination.
There is no known soil contamination and should not be
any potential contamination of nearby waterways.
Visual
1 Immediate line-of-site.
2 Distant skyline impact.
3 Distant impact due to lower site
elevation.
4 Surrounding area build-out.
Siting a new power plant in the proximity of U.S.
Highway 101 could have a clear and distinguishable
visual impact. Due to the height of the landfill (future
park) and the adjoining WWTP, the impact may be
somewhat diminished. The office complexes in the
general vicinity and along U.S. Highway 101 will also
help to offset visual impact. Visual impacts from the
Baylands Nature Preserve would also need to be
mitigated. If visual is a major issue, then architectural
amenities can be incorporated to make the facility
appear office like or some other more acceptable
appearance. The maximum stack height allowed to
meet city codes appears to be 75 feet above ground.
Further investigations to determine FAA restrictions are
required. A 50 MW facility should be able to comply with
this requirement.
Noise
1 At boundary.
2 Far field impacts.
3 Tonal potential impacts.
4 Mitigation required.
5 Mitigation capital cost.
6 Mitigation operating costs
Noise levels at the nearest sensitive receptors
(residential) should be at acceptable levels. Mitigation
may be required for the nearby office complex, future
park (current landfill), and the Baylands Nature Preserve.
PB Power, Inc.
WZI Inc.POTENTIAL SITE: PALO ALTO
13572 - 34 -
General Area Map
0'",10",;" * P, .. ;".S;t.l,,,t~"
".r "SG' T',OO"p'~"" """""~ "' .. & ,.~ "'to, CA
124000
'1\
S A
, -
,1' ,
.v A N C S c
B A Y
",lin
NCPA Site Selection Study
Possible Palo ;\Ito Site
PB Power, Inc.
WZI Inc.POTENTIAL SITE: PALO ALTO
13572 - 35 -
TABLE 1
RARE, THREATENED, ENDANGERED, AND SENSITIVE
ANIMALS, PLANTS, AND NATURAL COMMUNITIES
PALO ALTO AREA
List Status
NDDB Element
Ranks Other Lists
Scientific Name
Common Name
Federal
State Global State
Animals
Noted on Map
Athene Cunicularia
Burrowing Owl
None
None G4 S2 CDFG: SC
Geothlypis Trichas Sinuosa
Saltmarsh Common Yellowthroat
None
None G5T2 S2 CDFG: SC
Rallus Longirostris Obsoletus
California Clapper Rail
Endangered
Endangered G5T1 S1
Reithrodontomys Raviventris
Salt-Marsh Harvest Mouse
Endangered
Endangered G1G2 S1S2
Sterna Antillarum Browni
Califrornia Least Tern
Endangered
Endangered G4T2T3 S2S3
Also Noted in the Area
Ambystoma Californiense
California Tiger Salamander
Endangered1
None G2G3 S2S3 CDFG: SC
Charadrius Alexandrinus Nivosus
Western Snowy Plover
Threatened
None G4T2 S2 CDFG: SC
Circus Cyaneus
Northern Harrier
None
None G5 S3 CDFG: SC
Clemmys Marmorata
Western Pond Turtle
None
None G4 S3 CDFG: SC
Euphydryas Editha Bayensis
Bay Checkerspot Butterfly
Threatened
None G5T2 S2
Laterallus Jamaicensis Conturniculus
California Black Rail
None
Threatened G4T1 S1
Rana Aurora Draytonii
Foothill Red–legged Frog
Threatened
None G4T2T3 S2S3 CDFG: SC
Sorex Vagrans Halicoetes
Salt-Marsh Wandering Shrew
None
None G5T1 S1 CDFG: SC
Thamnophis Sirtalis Tetrataenia
San Francisco Garter Snake
Endangered
Endangered G5T2 S2
Plants
Noted on Map
Astragalus Tener var Tener
Alkali Milk-Vetch
None
None G1T1 S1.1 CNPS: 1B
RED: 3-2-3
Centromadia Parryi ssp Congdonii
Congdon’s Tarplant
None
None G5T1 S1.1 CNPS: 1B
RED: 3-3-3
Cordylanthus Maritimus ssp Palustris
Point Reyes Bird’s-Beak
None
None G3T2 S2.2 CNPS: 1B
RED: 2-2-2
Suaeda Californica
California Seablite
Endangered
None G1 S1.1 CNPS: 1B
RED: 3-3-3
Also Noted in the Area
Acanthomintha Duttonii
San Mateo Thorn-Mint
Endangered
Endangered G1 S1.1 CNPS: 1B
RED: 3-3-3
Allium Peninsulare var Franciscanum
Franciscan Onion
None
None G5T2 S2.2 CNPS: 1B
RED: 2-2-3
Dirca Occidentalis
Western Leatherwood
None
None G2G3 S2S3 CNPS: 1B
RED: 2-2-3
PB Power, Inc.
WZI Inc.POTENTIAL SITE: PALO ALTO
13572 - 36 -
List Status
NDDB Element
Ranks Other Lists
Scientific Name
Common Name
Federal
State Global State
Fritillaria Liliacea
Fragrant Fritillary
None
None G2 S2.2 CNPS: 1B
RED: 2-2-3
Hesperolinon Congestum
Marin Western Flax
Threatened
Threatened G2 S2.1 CNPS: 1B
RED: 3-3-3
Potamogeton Filiformis
Slender-Leaved Pondweed
None
None G5 S1S2 CNPS: 2
RED: 3-2-1
Tropidocarpum Capparideum
Caper-Fruited Tropidocarpum
None
None GH SH CNPS: 1A
RED: *
Serpentine Bunchgrass None G2 S2.2
Terrestrial Natural Community
Noted on Map
Northern Coastal Salt Marsh None G3 S3.2
Also Noted in the Area
Tryonia Imitator
Mimic Tryonia (=California Brackishwater
None
None G2G3 S2S3
Notes:1 Federal listing for California Tiger Salamander refers to populations in Santa Barbara County only.
Natural Diversity Database (NDDB) Element Ranks:
Global: The global rank (G–rank) is a reflection of the overall condition of an element throughout its global
range.
G1: Less than 6 viable element occurrences (EOs), or less than 1,000 individuals, or less than 2,000
acres.
G2: 6–20 EOs, or 1,000–3,000 individuals, or 2,000–10,000 acres.
G3: 21–100 EOs, or 3,000–10,000 individuals, or 10,000–50,000 acres.
G4: Apparently secure; this rank is clearly lower than G3 but factors exist to cause some concern; i.e.,
there is some threat, or somewhat narrow habitat.
G5: Population or stand demonstrably secure to ineradicable due to being commonly found in the world.
T rank: Subspecies receive a T–rank attached to the G–rank.
State: The state rank (S–rank) is assigned much the same as the global rank, except state ranks in
California often also contain a threat designation to the S–rank.
S1: Less than 6 EOs, or less than 1,000 individuals, or less than 2,000 acres.
S1.1: Very threatened
S1.2: Threatened
S1.3 No current threats known
S2: 6–20 EOs, or 1,000–3,000 individuals, or 2,000–10,000 acres.
S2.1: Very threatened
S2.2: Threatened
S2.3: No current threats known
S3: 21–100 EOs, or 3,000–10,000 individuals, or 10,00050,000 acres.
S3.1: Very threatened
S3.2: Threatened
S3.3: No current threats known
S4: Apparently secure within California; this rank is clearly lower than S3, but factors exist to cause
some concern; i.e., there is some threat, or somewhat narrow habitat. NO THREAT RANK.
S5: Demonstrably secure to ineradicable in California. NO THREAT RANK.
Uncertainty: Uncertainty about the rank of an element is expressed as a range (e.g., S2S3), or by adding a “?” to
the rank.
California Department of Fish and Game (CDFG)
SC: California Special Concern species.
PB Power, Inc.
WZI Inc.POTENTIAL SITE: PALO ALTO
13572 - 37 -
California Native Plant Society (CNPS)
1A: Plants presumed extinct in California.
1B: Plants rare, threatened, or endangered in California and elsewhere.
2: Plants rare, threatened, or endangered in California, but more common elsewhere.
3: Plants about which more information is required; a review list.
4: Plants of limited distribution; a watch list.
CNPS R–E–D Code
R – Rarity
1 Rare, but found in sufficient numbers and distributed widely enough that the potential for extinction is
low at this time.
2 Distributed in a limited number of occurrences, occasionally more if each occurrence is small.
3 Distributed in one to several highly restricted occurrences, or present in such small numbers that it is
seldom reported.
E – Endangerment
1 Not endangered.
2 Endangered in a portion of its range.
3 Endangered throughout its range
D – Distribution
1 More or less widespread outside California
2 Rare outside of California.
3 Endemic to California.
PB Power, Inc.
WZI Inc.POTENTIAL SITE: PALO ALTO
13572 - 38 -
Biological Resources Map
0 ' .... '.." .. D ........ ..,' .. ..,." .. ·, D · .... .....,' .. ..,." .. ·, H..!j, ........... " • ...,.""'., * ........ ",.-
D ... "...,,,...,.,, .. ••·• I' ,.~ .. ..,"'..,," ... ,
0 ....... ··" .. .."" .. •• ..
".r USGS T',OO""~"" ..,"""~ "ow & ,.~ "'''. CA
124000
, ,
S A ,V A N C s C
B A Y
NCPA Site Selection Study
Possible Palo ;\Ito Site
PB Power, Inc.
WZI Inc.POTENTIAL SITE: PALO ALTO
13572 - 39 -
Palo Alto Site Images
Looking W at landfill compost, WWTP, and recycling from landfill mound
Looking NE toward landfill and recycling center from utility road