This paper examines the economic potential for thermally-activated cooling (TAC) technologies as a component of distributed energy resource (DER) systems in California. A geographic information system (GIS) is used to assess the regional variation of TAC potential and to visualize the geographic pattern of potential adoption. The economic potential and feasibility of DER systems in general, and especially TAC, is highly dependent on regional factors such as retail electricity rates, building cooling loads, and building heating loads. Each of these factors varies with location, and their geographic overlap at different sites is an important determinant in a market assessment of DER and TAC. This analysis uses system payback period as the metric to show the regional variation of TAC potential in California office buildings. The DER system payback with and without TAC is calculated for different regions in California using localized values of retail electricity rates and the weather-dependent variation in building cooling and heating loads. This GIS-based method has numerous applications in building efficiency studies where geographically dependent variables, such as space cooling and heating energy use, play an important role.

This thesis focuses on the design of efficient, highly integrated antennas for millimeter- wave systems. Two gaps in the exisiting literature are addressed. First, the sinuous antenna on silicon dielectric lenses is explored. The antenna is demonstrated to be an excellent option for integrated systems requiring high-gain, dual-linear polarization, and a multi- octave bandwidth. A design with cross-pol below -17 dB, polarization variations less than ±5◦, and stable impedance properties over a 4:1 bandwidth is demonstrated.

Second, silicon RFIC antennas are studied, with the goal of achieving a high level of integration and a design scalable to frequencies beyond 100 GHz. A novel solution is proposed, which uses a dielectric superstrate layer to enhance the efficiency and gain of standard patch and elliptical slot antennas. Compared to a stand-alone W-band patch in a standard CMOS process, the proposed solution yields a 7 dB improvement in antenna efficiency. Because all of the metal layers are integrated on chip and the required dielectric layer is not electrically thin, the superstrate-loaded antennas are an excellent candidate for high-efficiency on-chip antennas beyond 100 GHz.

Hydrogen is emerging beyond its conventional role as an additive component for gasoline production, chemical and fertilizer manufacture, and food production to become a promising fuel for transportation and stationary power. Hydrogen offers a potentially unmatched ability to deliver a de-carbonized energy system, thereby addressing global climate change concerns, while simultaneously improving local air quality and reducing dependence on imported fossil fuels. This "trifecta" of potential benefits is sometimes missed by narrow "cost-effectiveness" analyses that examine any one of these benefits but ignore the others.

The emergence of a broader "hydrogen economy" can best be thought of as a transition that will take many years to unfold. Natural gas is a reasonable source of hydrogen in the near term, as it offers modest benefits and lower costs than most other sources. However, as the costs of hydrogen technologies such as fuel cells and electrolyzers decrease through mass production and technological learning, and costs of primary solar and wind power sources continue to slowly decrease, renewably-produced hydrogen will become more competitive.

Moreover, hydrogen costs will be relatively stable due to a diversity of feedstock base, with far more stable prices than the volatile oil and natural gas markets can offer. These reasons, coupled with the environmental benefits that hydrogen can offer if produced renewably and cleanly, have led most environmental advocates and states that are working to commercialize clean energy technologies to envision one articulated long-term scenario—a clean energy future that relies on fuel cells powered by renewably produced hydrogen.

Many states, particularly New York, Massachusetts, Connecticut, Florida, Michigan, Ohio and California, are providing research and project deployment funds, tax breaks for new industry, and other measures to encourage hydrogen and fuel cell developments in their states. These program incentives are based on the assumption that fuel cells and related hydrogen infrastructure development are likely to be important to a long-term, sustainable energy future, and that these technologies hold out hope for increased economic development in American industry. In fact, while the belief is hardly unanimous, many analysts and advocates have become convinced that fuel cells are one of the few "emission-free" technologies capable of fully transforming our energy system in a way that is urgently needed to stabilize greenhouse gas emissions and address climate change in the decades ahead.

In order to further explore the potential benefits that hydrogen can offer, we recommend a continued research and development effort, along with strategic demonstration and initial deployment efforts. Specifically, we offer the recommendations outlined in this report for consideration as a starting point for in-depth discussions that can lead to state-specific action plans and stakeholder engagement processes.

* Dedicate Significant Funding: State clean energy funds that currently support a broad suite of renewable energy technologies can commit significant, dedicated funding to develop action plans and programs that address the very real economic and technology barriers facing the production of hydrogen from renewable energy sources. In addition, there are significant opportunities to establish federal-state funding partnerships with agencies such as DOE, DOD and DHS that can leverage limited funding for hydrogen projects using renewable energy technologies. * Demonstrate the Viability of Hydrogen Storage and Production for Critical Applications: State clean energy funds and other public interest organizations have the opportunity to support projects that can demonstrate the viability of using hydrogen storage and energy conversion in critical applications, such as telecommunications and backup power, where on-site storage of hydrogen provides important power quality and security benefits. * Visibly Link Hydrogen Production and Clean Energy Technologies: Wind, photovoltaics and other projects that include clean energy technologies should be promoted as the preferred source of hydrogen production. Supporting projects that highlight the capability of producing hydrogen on-site from these sources will serve an important "ambassador" role, engendering important local and public support for hydrogen technologies. These projects can also support the acceptance of natural gas as an important transition fuel. Many states that currently support other clean energy technologies can seek opportunities to develop hybrid projects, linking together energy generation with hydrogen production and storage. * Establish Incentives for High-Value, On-Site Applications: Financial incentives that target specific applications of hydrogen technology can encourage both private and public-sector players to deploy hydrogen and fuel cell technologies. High-value and niche applications for production and use of hydrogen from renewable sources (such as backup power and battery replacement) may lead to self-sustaining markets important learning-by-doing benefits and increased public acceptance. * Proactively Address Regulatory Incentives: Advanced energy technologies can best be promoted with forward-thinking regulatory policies. Many states have implemented regulatory preferences and incentives (such as standby charge exemptions and net metering policies) that recognize and accommodate the public preference for and benefits from fuel cell, hydrogen and clean energy technologies. The regulatory strategies used by these early leaders can be replicated in other states. If hydrogen is to fulfill its role in a clean energy future, it will certainly be in conjunction with clean energy technologies that can operate in a distributed energy context. Currently, many regulatory barriers prevent the wide-scale adoption of clean distributed generation and limit the ability to store hydrogen on-site. These can be critical components of distributed generation projects that rely on hydrogen derived from renewable resources. * Accelerate Private Investment: Successfully deploying hydrogen technologies will require significant investment from the private sector. The introduction of new technologies entails crossing what has come to be called "the valley of death"—the need for capital investments to take promising technologies from the invention and technology validation stage to the point of initial demonstration, field testing, and commercialization. These early investments can be accelerated with preferential tax treatment and other incentives to judiciously use public resources to assist and share risks with industry to develop new energy solutions. Florida, for example, has proposed significant tax benefits that could accelerate ongoing investments by Fortune 100 companies such as the recent investments by Sprint in fuel cell systems. States should consider enacting similar favorable tax policies and exemptions for projects developing hydrogen from renewable resources. * Develop Compelling Communications Strategies: The potential use of hydrogen outside of the industrial sector has been hampered by public misperceptions and lack of awareness of its significant benefits. In recent years, many states have conducted sophisticated consumer and stakeholder research that has resulted in new communications campaigns to increase public understanding and support for clean energy technologies. Many states, for example, recently joined together to develop and fund a "Clean Energy: It's Real, It's Here, It's Working. Let's Make More" branding campaign. This kind of proactive communications strategy could yield tremendous results for the hydrogen sector, helping to organize currently disparate enthusiasm for hydrogen with a single, compelling message.

Small-scale (100 kW-5 MW) on-site distributed generation (DG) economically driven by combined heat and power (CHP) applications and, in some cases, reliability concerns will likely emerge as a common feature of commercial building energy systems in developed countries over the next two decades. In the U.S., private and public expectations for this technology are heavily influenced by forecasts published by the Energy Information Administration (EIA), most notably the Annual Energy Outlook (AEO). EIA's forecasts are typically made using the National Energy Modeling System (NEMS), which has a forecasting module that predicts the penetration of several possible commercial building DG technologies over the period 2005-2025. Annual penetration is forecast by estimating the payback period for each technology, for each of a limited number of representative building types, for each of nine regions. This process results in an AEO2004 forecast deployment of about a total 3 GW of DG electrical generating capacity by 2025, which is only 0.25 percent of total forecast U.S. capacity. Analyses conducted using both the AEO2003 and AEO2004 versions of NEMS changes the baseline costs and performance characteristics of DG to reflect a world without U.S. Department of Energy (DOE) research into several thermal DG technologies, which is then compared to a case with enhanced technology representative of the successful achievement of DOE research goals. The net difference in 2025 DG penetration is dramatic using the AEO2003 version of NEMS, but much smaller in the AEO2004 version. The significance and validity of these contradictory results are discussed, and possibilities for improving estimates of commercial U.S. DG potential are explored.

The market for small wind systems in the United States, often defined as systems less than or equal to 100 kW that produce power on the customer side of the meter, is small but growing steadily. The installed capacity of domestic small wind systems in 2002 was reportedly 15-18 MW, though the market is estimated to be growing by as much as 40 percent annually (AWEA, 2002). This growth is driven in part by recent technology advancements and cost improvements and, perhaps more importantly, by favorable policy incentives targeted at small wind systems that are offered in several states. Currently, over half of all states have incentive policies for which residential small wind installations are eligible. These incentives range from low-interest loan programs and various forms of tax advantages to cash rebates that cover as much as 60 percent of the total system cost for turbines 10 kW or smaller installed in residential applications. Most of these incentives were developed to support a range of emerging renewable technologies (most notably photovoltaic systems), and were therefore not specifically designed with small wind systems in mind. As such, the question remains as to which incentive types provide the greatest benefit to small wind systems, and how states might appropriately set the level and type of incentives in the future. Furthermore, given differences in incentive types and levels across states, as well as variations in retail electricity rates and other relevant factors, it is not immediately obvious which states offer the most promising markets for small wind turbine manufacturers and installers, as well as potential residential system owners. This paper presents results from a Berkeley Lab analysis of the impact of existing and proposed state and federal incentives on the economics of grid-connected, residential small wind systems. Berkeley Lab has designed the Small Wind Analysis Tool (SWAT) to compare system economics under current incentive structures across all 50 states. SWAT reports three metrics to characterize residential wind economics in each state and wind resource class: - Break-Even Turnkey Cost (BTC): The BTC is defined as the aggregate installed system cost that would balance total customer payments and revenue over the life of the system, allowing the customer to "break-even" while earning a specified rate of return on the small wind "investment." - Simple Payback (SP): The SP is the number of years it takes a customer to recoup a cash payment for a wind system and all associated costs, assuming zero discount on future revenue and payments (i.e., ignoring the time value of money). - Levelized Cost of Energy (LCOE): The LCOE is the levelized cost of generating a kWh of electricity over the lifetime of the system, and is calculated assuming a cash purchase for the small wind system and a 5.5 percent real discount rate. This paper presents SWAT results for a 10 kW wind turbine and turbine power production is based on a Bergey Excel system. These results are not directly applicable to turbines with different power curves and rated outputs, especially given the fact that many state incentives are set as a fixed dollar amount, and the dollar per Watt amount will vary based on the total rated turbine capacity.

Although small wind turbine technology and economics have improved in recent years, the small wind market in the United States continues to be driven in large part by state incentives, such as cash rebates, favorable loan programs, and tax credits. This paper examines the state-by-state economic attractiveness of small residential wind systems. Economic attractiveness is evaluated primarily using the break-even turnkey cost (BTC) of a residential wind system as the figure of merit. The BTC is defined here as the aggregate installed cost of a small wind system that could be supported such that the system owner would break even (and receive a specified return on investment) over the life of the turbine, taking into account current available incentives, the wind resource, and the retail electricity rate offset by on-site generation. Based on the analysis presented in this paper, we conclude that: (1) the economics of residential, grid-connected small wind systems is highly variable by state and wind resource class, (2) significant cost reductions will be necessary to stimulate widespread market acceptance absent significant changes in the level of policy support, and (3) a number of policies could help stimulate the market, but state cash incentives currently have the most significant impact, and will be a critical element of continued growth in this market.

This report describes Berkeley Lab's exploration of how the National Energy Modeling System (NEMS) models distributed generation (DG) and presents possible approaches for improving how DG is modeled. The on-site electric generation capability has been available since the AEO2000 version of NEMS. Berkeley Lab has previously completed research on distributed energy resources (DER) adoption at individual sites and has developed a DER Customer Adoption Model called DER-CAM. Given interest in this area, Berkeley Lab set out to understand how NEMS models small-scale on-site generation to assess how adequately DG is treated in NEMS, and to propose improvements or alternatives. The goal is to determine how well NEMS models the factors influencing DG adoption and to consider alternatives to the current approach. Most small-scale DG adoption takes place in the residential and commercial modules of NEMS. Investment in DG ultimately offsets purchases of electricity, which also eliminates the losses associated with transmission and distribution (T&D). If the DG technology that is chosen is photovoltaics (PV), NEMS assumes renewable energy consumption replaces the energy input to electric generators. If the DG technology is fuel consuming, consumption of fuel in the electric utility sector is replaced by residential or commercial fuel consumption. The waste heat generated from thermal technologies can be used to offset the water heating and space heating energy uses, but there is no thermally activated cooling capability. This study consists of a review of model documentation and a paper by EIA staff, a series of sensitivity runs performed by Berkeley Lab that exercise selected DG parameters in the AEO2002 version of NEMS, and a scoping effort of possible enhancements and alternatives to NEMS current DG capabilities. In general, the treatment of DG in NEMS is rudimentary. The penetration of DG is determined by an economic cash-flow analysis that determines adoption based on the number of years to a positive cash flow. Some important technologies, e.g. thermally activated cooling, are absent, and ceilings on DG adoption are determined by some what arbitrary caps on the number of buildings that can adopt DG. These caps are particularly severe for existing buildings, where the maximum penetration for any one technology is 0.25 percent. On the other hand, competition among technologies is not fully considered, and this may result in double-counting for certain applications. A series of sensitivity runs show greater penetration with net metering enhancements and aggressive tax credits and a more limited response to lowered DG technology costs. Discussion of alternatives to the current code is presented in Section 4. Alternatives or improvements to how DG is modeled in NEMS cover three basic areas: expanding on the existing total market for DG both by changing existing parameters in NEMS and by adding new capabilities, such as for missing technologies; enhancing the cash flow analysis but incorporating aspects of DG economics that are not currently represented, e.g. complex tariffs; and using an external geographic information system (GIS) driven analysis that can better and more intuitively identify niche markets.