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Nielson, Gregory

Publications and source records attributed to Nielson, Gregory.

Revisiting the Effects of Photovoltaic Module Efficiency on Installed System Cost and Market Adoption

We conduct bottom-up analysis of how PV module efficiency could influence residential rooftop installed system costs, using models with improved representation of how soft costs and power electronics are affected by efficiency. We show that the amount of system installed cost savings resulting from high efficiency modules depends on whether or not the system is area-constrained, with much larger savings for the area-constrained case. We then estimate the fraction of physically area-constrained rooftops in the United States to be 61%, with variation between 20% to over 80% of rooftops depending on the state. We find that fraction of area-constrained systems could grow to over 88% by 2050 if building and transportation loads are electrified.

efficiency↗

The Effect of Photovoltaic Module Efficiency on Installed System Costs and Markets in Residential Rooftop Installations in the United States

In this report, we analyze how efficiencies influence residential PV system installed system costs and break-even module prices using a bottom-up cost model. We show that the cost savings associated with efficiency are much higher for area-constrained rooftop than those which are usage-constrained. We also show that simplified models of how efficiency impacts costs overestimate the value of efficiency compared to bottom-up models, particularly for usage-constrained scenarios. We also estimate the fraction of area-constrained residential rooftops in the United States today and explore how that fraction could change in future scenarios with high levels of electrification.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Hybrid Integration of III-V Solar Microcells for High Efficiency Concentrated Photovoltaic Modules

The design, fabrication and performance of InGaAs and InGaP/GaAs microcells are presented. These cells are integrated with a Si wafer providing a path for insertion in hybrid concentrated photovoltaic modules. Comparisons are made between bonded cells and cells fabricated on their native wafer. The bonded cells showed no evidence of degradation in spite of the integration process which involved significant processing including the removal of the III-V substrate. Results from a number of hybrid cell configurations were reported. These cells employed integration techniques including wafer level bonding of processed cells and solder bonding of the cells. Lastly, the cells themselves showed evidence of degradation in spite of the integration process, which involved significant processing including the removal of the III-V substrate.

14 SOLAR ENERGY↗

Final Report MEPV

The MEPV Grand Challenge was focused on exploiting beneficial scaling effects in solar cells, modules, and systems to make solar power the lowest cost source of power available. The project explored new multijunction, microscale solar cell architectures, new micro-optical concentration methods, new hybrid solar collection concepts, and developed a series of prototypes to demonstrate these technologies. In addition, a detailed cost analysis was conducted to determine the costs of the proposed technologies and provide guidance for the system design efforts. Key results included demonstration of InGaP/GaAS cells transferred to active silicon cells to create a three junction cell with efficiency near 30%, the transfer of InGaAs cells to Si with demonstrated high performance of the InGaAs cell behind the Si substrate, the design, manufacture, and experimental demonstration of optics with almost 90% transmission efficiency and 100X and 200X concentration with a relatively large acceptance angle (>±1.5°), and the full assembly and demonstration of functional microconcentrator systems. The cost modeling efforts indicated that a module based on the best design resulting from the knowledge and technology develop would approach $1/Wpeak total installed system cost with no subsidies. If achieved in practice, this system would provide the lowest energy cost of any grid-tied energy source.

14 SOLAR ENERGY↗