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DOE OSTI2025

2019 and 2022 Twin Cities Travel Behavior Inventory Surveys

# 2019 and 2022 Twin Cities Travel Behavior Inventory Surveys To help local and regional planning agencies understand shifting demographics and travel patterns, surveys were conducted in Minnesota’s greater Twin Cities region in 2019 and 2022. Survey results aided the Metropolitan Council in proposing practical transportation investments, preparing competitive grant applications, and prioritizing improvements to best fit regional needs. ## Data Collection Agency RSG conducted the surveys for the Metropolitan Council. ## Survey Methodology These mixed-mode surveys focused on bus, rail, car, micromobility, ride-hailing, and walking. Designed as household travel surveys, they were carried out in English, Spanish, Karen, Oromo, Somali, and Hmong during two timeframes: Oct. 1, 2018—Sept. 30, 2019 and June 22, 2021—Feb. 5, 2022. Participants accessed the surveys using a smartphone-based app, website, or call center. A questionnaire captured data about demographics, daily travel activities, and typical transportation patterns to inform model updates and gain information about emerging behavioral changes such as electric vehicle adoption and teleworking frequency. It also addressed the impacts of COVID-19 on participants’ typical travel behavior. ## Survey Records, Data, and Documentation Survey records include a total of 31,251 participants—16,152 participants from 7,837 households during the 2019 survey and 15,099 participants from 7,952 households during the 2022 survey.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

DOE OSTI2025

2019 and 2022 Twin Cities Travel Behavior Inventory Surveys

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

DOE OSTI2014

City of Phoenix - Energize Phoenix Program

Energize Phoenix (EPHX) was designed as an ambitious, large-scale, three-year pilot program to provide energy efficiency upgrades in buildings, along Phoenix’s new Light Rail Corridor – part of a federal effort to reduce energy consumption and stimulate job growth, while simultaneously reducing the country’s carbon footprint and promoting a shift towards a green economy. The program was created through a 2010 competitive grant awarded to the City of Phoenix who managed the program in partnership with Arizona State University (ASU), the state’s largest university, and Arizona Public Service (APS), the state’s largest electricity provider. The U.S. Department of Energy (DOE) Better Buildings Neighborhood Program (BBNP) and the American Recovery and Reinvestment Act (ARRA) of 2009 provided $25M in funding for the EPHX program. The Light Rail Corridor runs through the heart of downtown Phoenix, making most high-rise and smaller commercial buildings eligible to participate in the EPHX program, along with a diverse mix of single and multi-family residential buildings. To ensure maximum impact and deeper market penetration, Energize Phoenix was subdivided into three unique parts: i. commercial rebate program, ii. commercial financing program, and iii. residential program Each component was managed by the City of Phoenix in partnership with APS. Phoenix was fortunate to partner with APS, which already operated robust commercial and residential rebate programs within its service territory. Phoenix tapped into the existing utility contractor network, provided specific training to over 100 contracting firms, and leveraged the APS rebate program structure (energy efficiency funding) to launch the EPHX commercial and residential rebate programs. The commercial finance program was coordinated and managed through a contract with National Bank of Arizona, NBAZ, which also provided project capital leveraging EPHX finance funds. Working in unison, approved contractors jointly produced more than 161,000 labor hours in pursuit of EPHX goals over the life of the project. Labor hours were spread among electricians, heating, ventilating and air-conditioning (HVAC) technicians, marketing professionals, engineers, sales, and administrative support staff across the approved contractor workforce. Program participants received both the utility rebate along with the EPHX rebate, and depending on project size and utility rebate structure some projects resulted in low to no-cost upgrades for customers. Phoenix also partnered with ASU, a grant sub-recipient, to leverage the institution’s expertise in research and data analysis. In this partnership, ASU accepted marketing responsibilities for the grant and partnered with DRA Communications (DRA), a Phoenix-based marketing firm, to create and communicate the message out to the marketplace. The EPHX program has completed its energy upgrade activities. A review of the work completed by ASU revealed that the EPHX program substantially exceeded the program’s stated goals by retrofitting/upgrading over 33 million sq ft of commercial space (30 million sq ft goal exceeded by 11%) and 2,014 residential units (1,700 unit goal exceeded by 18%) along the Light Rail Corridor. The program helped stimulate economic growth by adding $31million to the local economy and enhanced an already robust energy efficiency contractor network. This contractor network will continue to promote utility energy incentives to sustain energy efficiency upgrade activities in the future. Finally, EPHX helped reduce participants annual energy consumption by 135 million kilowatt-hour (kWh) translating into over $12.5 million of annual energy cost avoidance for the community. This also resulted in projected payback period of 4.5 years for total investment by all parties and reduced greenhouse gas emissions by over 95,000 metric tons of carbon dioxide equivalent (CO2e).

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

DOE OSTI2014

City of Hoboken Energy Surety Analysis: Preliminary Design Summary

In 2012, Hurricane Sandy devastated much of the U.S. northeast coastal areas. Among those hardest hit was the small community of Hoboken, New Jersey, located on the banks of the Hudson River across from Manhattan. This report describes a city-wide electrical infrastructure design that uses microgrids and other infrastructure to ensure the city retains functionality should such an event occur in the future. The designs ensure that up to 55 critical buildings will retain power during blackout or flooded conditions and include analysis for microgrid architectures, performance parameters, system control, renewable energy integration, and financial opportunities (while grid connected). The results presented here are not binding and are subject to change based on input from the Hoboken stakeholders, the integrator selected to manage and implement the microgrid, or other subject matter experts during the detailed (final) phase of the design effort.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

DOE OSTI2015

Research, Development and Demonstration of Peak Load Reduction on Distribution Feeders Using Distributed Energy Resources for the City of Fort Collins

This project titled “Research, Development and Demonstration of Peak Load Reduction on Distribution Feeders Using Distributed Energy Resources for the City of Fort Collins” evolved in response to the Department of Energy’s (DOE) Funding Opportunity Announcement (FOA) Number DE-PS26-07NT43119. Also referred to as the Fort Collins Renewable and Distributed System Integration (RDSI) Project, the effort was undertaken by a diverse group of local government, higher education and business organizations; and was driven by three overarching goals: I. Fulfill the requirements of the DOE FOA’s Area of Interest 2: Renewable and Distributed System Integration; most notably, to demonstrate the ability to reduce electric system distribution feeder peak load by 15% or more through the coordinated use of Distributed Energy Resources (DER). II. Advance the expertise, technologies and infrastructure necessary to support the long term vision of the Fort Collins Zero Energy District (FortZED) and move towards creating a zero energy district in the Fort Collins “Old Town” area. III. Further the goals of the City of Fort Collins Energy Policy, including the development of a Smart Grid-enabled distribution system in Fort Collins, expanded use of renewable energy, increased energy conservation, and peak load reduction. Through the collaborative efforts of the partner organizations, the Fort Collins RDSI project was successful in achieving all three of these goals. This report is organized into two distinct sections corresponding to the two phases of the project: • Part 1: Feeder Peak Load Reduction and the FortZED Initiative. • Part 2: Forming and Operating Utility Microgrids and Managing Load and Production Variability The original project scope addressed the Part 1 feeder peak load reduction. That work took place from 2009 through 2011 and was largely complete when the project scope was amended to include a demonstration of microgrid operations. While leveraging the assets, partner relationships, and lessons learned from Part 1, Part 2 was managed and executed as a distinct and substantially independent sub-project during the spring and summer of 2013. Both Parts 1 and 2 of the overall RDSI project can be viewed as cohesive stand-alone bodies of work and are presented as such within this report. In addition to the narratives, this document includes two Appendices that were compiled to supplement information about the various aspects of activities performed during Parts 1 and 2 of the project. Moreover, these Appendices are organized (as outlined below) so as to directly relate to the narratives in Part 1 and 2 of this report. • Appendix - Part 1: describes the roles of each project participant in regards to the feeder peak load reduction effort, and • Appendix - Part 2: deals with the microgrid research/demonstration.

14 SOLAR ENERGY↗

DOE OSTI2018

The Case for All New City Buses in India to be Electric

Indian cities are struggling to keep the air breathable for inhabitants, due in part to emissions from diesel buses. While the case for electric buses, and more generally, zero emission buses, has always been clear from an urban air pollution perspective, the economic case depended strongly on their environmental benefits. However, the situation seems different today. We illustrate that when the benefits of recent dramatic declines in Lithium battery prices are fully realized, the total cost of ownership of urban (intra-city) electric buses is lower than that for diesel buses in India even without subsidies. Factoring in the air quality benefits, projected reductions in the cost of batteries and solar electricity, it becomes evident that transitioning to an all-electric bus fleet presents an enormous opportunity for India to reduce urban air pollution while improving the finances of urban bus transit agencies. The policy ecosystem that delivered substantial price reductions and large-scale rapid deployment of solar PV and LEDs is a model to achieve similar outcomes for battery electric buses. Well-designed high volume auctions and clear long term ambitious targets for fleet electrification could achieve to rapid electrification with little net public subsidy in the long-run.

33 ADVANCED PROPULSION SYSTEMS↗

DOE OSTI2019

Life cycle cost analysis comparing redesigned CCHP to existing heat pump systems for cities in cold climates

This report indicates that the project progress has met the Go criterion, i.e. demonstrating favorable results of life cycle cost assessment for the redesigned CCHPs. Considering the market price of a baseline heat pump, and required improvements in heat exchangers, fans and an electronic expansion valve of the CCHPs, we estimated that the CCHP using a 3-stage scroll compressor will incur with a cost increment of $\$386$ per rated cooling tonnage, and the CCHP using tandem compressors will increase by $\$770$. Based on the energy savings of the CCHPs, simulated by EnergyPlus, the two CCHPs achieve payback periods less than 4 years among all the cold climate cities. Within a typical heat pump life cycle of 20 years, the CCHPs can achieve cost savings around $\$2000$ per rated cooling tonnage, and the savings are even higher for the extremely cold cities like Duluth and Fairbanks.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

DOE OSTI2021

City-Wide Distributed Roof-Top Photovoltaic System Adoption Forecast, Grid Impact Simulation, & Neighborhood Microgrid Contribution Assessment

The adoption of distributed photovoltaic (PV) systems grew significantly in recent years. Market projections anticipate future growth for both residential and commercial installations. To understand grid impacts associated with distributed PV, useful hosting capacity studies require accurate representations of the spatial distribution of PV adoptions. Prediction of PV locations and numbers depends on median income data, building use zoning maps, and permit records to understand existing trends and predict future adoption rates and locations throughout an entire city. Using the PV adoption data, advanced and realistic simulations were performed to capture the distributed PV impacts on the grid. Also, using graph theory community detection hundreds of neighborhood microgrids can be discovered for the entire city by identifying densely connected loads that are sparsely connected to other communities. Then, based on the PV adoption predictions, this work identified the contribution of PV within each of the newly discovered graph theory defined microgrid communities.

24 POWER TRANSMISSION AND DISTRIBUTION↗

DOE OSTI2021

City of Largo Clear Sky Assessment Process: Prioritizing Solar + Storage for Resilient Facilities & Communities

The Clear Sky Tampa Bay project was a 15-month collaborative research effort to support solar + storage deployment for community resilience in Florida. The Clear Sky Decision Support Toolkit is a collection of resources designed to support users in conducting solar + storage prioritization and feasibility screening assessments at critical facilities. The Tampa Bay Regional Planning Council worked with four local governments in the region to test and apply the Toolkit. This case study series describes how each partner government used the Toolkit and highlights key insights and lessons learned that other users could follow to replicate the process. The City of Largo used the Clear Sky Decision Support Toolkit to advance community solar + storage resilience goals by collaborating with staff across departments and disciplines and engaging with utility stakeholders. The City of Largo conducted an analysis of its Wastewater Treatment Facility (WWTF), which processes an average of 43 million gallons of wastewater daily. Water treatment operations are both critical and energy intensive, requiring sustained energy throughout the day.

14 SOLAR ENERGY↗

DOE OSTI2020

City-Scale Building Anthropogenic Heating during Heat Waves

More frequent and longer duration heat waves have been observed worldwide and are recognized as a serious threat to human health and the stability of electrical grids. Past studies have identified a positive feedback between heat waves and urban heat island effects. Anthropogenic heat emissions from buildings have a crucial impact on the urban environment, and hence it is critical to understand the interactive effects of urban microclimate and building heat emissions in terms of the urban energy balance. Here we developed a coupled-simulation approach to quantify these effects, mapping urban environmental data generated by the mesoscale Weather Research and Forecasting (WRF) coupled to Urban Canopy Model (UCM) to urban building energy models (UBEM). We conducted a case study in the city of Los Angeles, California, during a five-day heat wave event in September 2009. We analyzed the surge in city-scale building heat emission and energy use during the extreme heat event. We first simulated the urban microclimate at a high resolution (500 m by 500 m) using WRF-UCM. We then generated grid-level building heat emission profiles and aggregated them using prototype building energy models informed by spatially disaggregated urban land use and urban building density data. The spatial patterns of anthropogenic heat discharge from the building sector were analyzed, and the quantitative relationship with weather conditions and urban land-use dynamics were assessed at the grid level. The simulation results indicate that the dispersion of anthropogenic heat from urban buildings to the urban environment increases by up to 20% on average and varies significantly, both in time and space, during the heat wave event. The heat dispersion from the air-conditioning heat rejection contributes most (86.5%) of the total waste heat from the buildings to the urban environment. We also found that the waste heat discharge in inland, dense urban districts is more sensitive to extreme events than it is in coastal or suburban areas. The generated anthropogenic heat profiles can be used in urban microclimate models to provide a more accurate estimation of urban air temperature rises during heat waves.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

DOE OSTI2026

Technoeconomic Opportunity Analysis for Local Power Generation in Falls City, Nebraska

Falls City is a small community in Nebraska interested in understanding how energy from local energy systems could support the community's economic development planning. To address the current community needs and address the future energy demand technical assistance conducted through the Communities Local Energy Action Program (Communities LEAP) assessed the technical and economic opportunities of adding energy technologies to Falls City's municipally owned and operated electric utility system. The modeling performed considered the technical and economic feasibility of technologies using the System Advisor Model (SAM). The modeling explored three technology configurations using multiple years of historical weather and wholesale cost data (2015-2022 & a typical meteorological year), and two different wholesale escalation rates (0.3% and 2.5%). Wholesale energy prices were based on the Southwest Power Pool's (SPP) real-time energy market and the annual escalation rates of these rates based on historical SPP wholesale and national retail electricity price trends. Results from the modeling showed that at current CAPEX costs and SPP wholesale electricity costs no technology combination averaged across the scenarios run provide a positive net present value (NPV). External financial support, changes in market conditions, and additional revenue streams would help create more economically favorable projects. As conditions change re-evaluation may be necessary.

24 POWER TRANSMISSION AND DISTRIBUTION↗

DOE OSTI2021

Block Scale Rooftop Solar Technical Potential for the City of Orlando

The html maps are provided as supplementary information for the publication titled Parcel Scale Assessment of Rooftop Solar Technical Potential (NREL/PR-7A40-80780). The maps contain information on rooftop solar technical potential at the block scale for the city of Orlando in Florida. The rooftop solar technical potential information is based on data from two different datasets. The first dataset is LiDAR data for the city of Orlando obtained from the Orlando Utilities Commission (OUC) (Koebrich et al. 2021). The second dataset is a national parcel dataset (HIFLD 2020) which contains descriptive data and geometries for parcels in the U.S. Parcel scale data from both these datasets have been processed and aggregated to block scale to produce these html maps. The first html map (block scale developable roof area for Orlando) contains the developable roof area for solar. The second html map (block scale rooftop solar technical potential for Orlando) contains the rooftop solar technical potential in units of kilowatts as well as additional information on the most common building use type and the most common building occupancy type for the block. These html maps are provided to demonstrate the proof-of-concept analysis conducted for Orlando.

14 SOLAR ENERGY↗

NASA NTRS1973

Urban and regional land use analysis: CARETS and Census Cities experiment package

The author has identified the following significant results. The arrival of the so-called energy crisis makes the portion of this experiment dealing with land use climatology of more immediate significance than before, since in addition to helping to understand the processes of climatic change associated with urbanization, the knowledge obtained may be useful in assigning an energy balance impact factor to proposed changes in land use in and around cities. Thermal maps derived from S-192 data are to be used as a measure of the energy being radiated into space from the mosaic of different surfaces in and around the city. While presenting excellent spatial sampling potential for a metropolitan area tests site, the Skylab data permit a very poor temporal sampling opportunity, owing to the large number of factors beyond the investigator's control that determine when data will be taken over a given test site. The strategy is to augment the thermal maps derived from S-192 with a modeling technique which enables the simulation of a number of components of the surface energy balance, calculated at regular time intervals throughout the day or year. Preliminary tests on the performance of the model are still underway, using airborne MSS data from NASA aircraft flights. Results look extremely promising.

Alexander, R. H.↗

NASA NTRS1974

California four cities program, 1971 - 1973

A pilot project in aerospace-to-urban technology application is reported. Companies assigned senior engineering professionals to serve as Science and Technology Advisors to participating city governments. Technical support was provided by the companies and JPL. The cities, Anaheim, Fresno, Pasadena, and San Hose, California, provided the working environment and general service support. Each city/company team developed and carried out one or more technical or management pilot projects together with a number of less formalized technology efforts and studies. An account and evaluation is provided of the initial two-year phase of the program.

Macomber, H. L.↗

NASA NTRS1975

The resonant orbit of the Lost City meteorite

An integration of the long-period perturbations of Jupiter and Saturn on the orbit of the Lost City meteorite shows that the average nodal rate of the meteorite was nearly the same as the nodal rates of Jupiter and Saturn. This near equality of rates led to a large resonant variation in the inclination of the meteorite's orbit with a period on the order of 1 million years. The resonance makes the orbital evolution too sensitive to the deficiencies of the perturbation calculations and to the values of the elements at impact to allow definitive calculations. It is shown that an orbit similar to the meteorite's orbit can spend approximately 88% of its time with an eccentricity too small to allow for intersections with the earth's orbit. The ordinary cosmic ray exposure age of the Lost City meteorite does not suggest that its collisional lifetime was unusual, but the role of resonances in determining the lifetime of typical meteorites is unknown.

Williams, J. G.↗

NASA NTRS1976

Conversion of prime agricultural land to urban land uses in Kansas City

In an expanding urban environment, agriculture and urban land uses are the two primary competitors for regional land resources. As a result of an increasing awareness of the effects which urban expansion has upon the regional environment, the conversion of prime agricultural land to urban land uses has become a point of concern to urban planners. A study was undertaken for the Kansas City Metropolitan Region, to determine the rate at which prime agricultural land has been converted to urban land uses over a five year period from 1969 to 1974. Using NASA high altitude color infrared imagery acquired over the city in October, 1969 and in May, 1974 to monitor the extent and location of urban expansion in the interim period, it was revealed that 42% of that expansion had occurred upon land classified as having prime agricultural potential. This involved a total of 10,727 acres of prime agricultural land and indicated a 7% increase over the 1969 which showed that 35% of the urban area had been developed on prime agricultural land.

Shaklee, R. V.↗

NASA NTRS1986

Detection of hydrothermal alteration at Virginia City, Nevada using Airborne Imaging Spectrometry (AIS)

Airborne Imaging Spectrometer (AIS) data were collected over Virginia City, Nevada; an area of gold and silver mineralization with extensive surface exposures of altered volcanic rocks. The data were corrected for atmospheric effects by a flat-field method, and compared to library spectra of various alteration minerals using a spectral analysis program SPAM. Areas of strong clay alteration were identified on the AIS images that were mapped as kaolinitic, illitic, and sericitic alterations zones. Kaolinitic alteration is distinguishable in the 2.1 to 2.4 and 1.2 to 1.5 micrometer wavelength regions. Montmorillonite, illite, and sericite have absorption features similar to each other at 2.2 micrometer wavelength. Montnorillonite and illite also may be present in varying proportions within one Ground Instantaneous Field of View (GIFOV). In general AIS data is useful in identifying alteration zones that are associated with or lie above precious metal mineralization at Virginia City.

Hutsinpiller, A.↗

NASA NTRS1989

Central electrical utility power for a satellite ring city in low earth orbit space

Information is given in viewgraph form on central electrical power for a satellite ring city, defined as a group of large free flyers of 10 to 20 units with perhaps 100 people in each unit, and organized in a circle so that power can be fed from a central location. The free flyers would be located at 300 to 700 miles in altitude, and spaced about a kilometer apart. Potential activities of a ring city are listed as well as the electrical power needs. Information is given on costs and individual and centralized solar arrays and nuclear reactor systems.

Myers, Ira T.↗