One contributor to this decline is consumer sentiment about EVs, “...the average consumer, according to surveys, would not even consider purchasing an electric vehicle, demonstrating that the technology is not yet at that tipping point where it's on a certain path towards market dominance.” This is just one example highlighting why alternative energy use remains insignificant in the U.S. regardless of the benefits, incentives and social prestige promised by its advocates. As an extension to one of the primary goals of an EV, charging its batteries with clean renewable energy, solar generated electricity shares the same fate.

While solar energy use in its thermal form focusing sunlight to accumulate heat energy in targeted transfer medium(s) dates back as early as the 7th century B.C., the electrical form utilizing the photovoltaic (PV) effect used by today’s solar panels was not discovered until 1839 with its first effective deployment over 100 years later in 1954 where PV cells where deployed to power U.S. space satellites. Enjoying increases of 25% and 32% year-over-year for 2019 and 2020 respectively, as of 2020, the U.S. Energy Information Administration estimates that 130 billion kilowatt-hours (electrical measure of power generation) was produced by PV generation plants ranging from small residential systems to large utility-scale facilities. As impressive as this metric seems to be, it only represents a contribution of 0.46% of the U.S. electricity generation for the same year. Obviously, PV has a long way to go before it will have any significant impact on the aforementioned concerns. This research seeks to identify targeted opportunities to improve outcomes in these areas as it relates to solar-generated electricity.

EV and PV see significant support through federal, state and local incentive programs, which are substantially responsible for the exponential growth of the adoption of these respective technologies. Conversely, competing technologies are encountering a growing trend of disincentives ranging from increased cost of ownership, regulatory burdens, and outright banned use. Public exposure to the potential environmental impacts regarding the use of these energy alternatives is equally compelling. Production costs continue to decline, efficiency and purchase options continue to increase. According to the U.S. Energy Information Administration (EIA), as of the end of 2021, EVs enjoyed a 10% market share for light duty vehicle sales in the U.S. The International Energy Agency (IEA) in its “Global EV Outlook 2021” documented 10 million electric cars on the world’s roads in 2020 calling it a “pivotal year for the electrification of mass market transportation.” This represented about 4.6% of total cars sales worldwide. Worldwide, 14 billion USD was provided on direct purchase incentives and tax deduction for electric cars in 2020, a 25% rise year-on-year. Financial incentives in the U.S. originated in 2008 and have grown substantially through the present. PV has a comparable heritage. The International Renewable Energy Agency (IRENA) reported that 128 billion USD was provided to the renewable power generation sector to incentivize its propagation worldwide in 2017. According to the Center for Sustainable Systems of the University of Michigan, in 2011 the U.S. Department of Energy (DOE) launched the SunShot Initiative with the intent to reduce the cost of solar energy by 75% making it competitive with other energy options. The 2020 target of $0.06 per kilowatt hour was reached three years early in 2017 and the 2030 goal is set at $0.03 per kilowatt hour.

Again, this pursuit is cumulative in that it would be considered in addition to, not in lieu of, existing policy, but involving a philosophical return to the origins of the technologies and what led to their original discoveries. According to the National Aeronautics and Space Administration (NASA), approximately 85% of all small satellites are equipped with solar panels and rechargeable batteries. This is predominantly due to the incapacity of competing energy sources being deployed and/or sustained on such craft. Subsequently, PV is inherently superior and frequently the only solution available. This “inherently superior” concept has always existed, but has been overlooked to a consequential degree by consumption habits and competing technologies that have been deeply rooted into every aspect of modern U.S. life. As the late 19th century battle of large scale electricity generation and distribution was ultimately won by Tesla’s alternating current (AC) designs, today’s consumption and proliferation of direct current (DC) devices has tipped the scales to such a degree it substantiates paradigm shift prompting a reconsideration of the modern day electrical grid with the influence of Thomas Edison’s DC designs. Tesla’s AC designs were and are inherently superior for large scale power generation, transmission, and use due to its ability to deliver power over greater distances with greater efficiency. The immense existence of DC powered electronics that continues to increase at a phenomenally rampant pace underscores a reconsideration of the AC/DC equation.

Any conversion of energy from one form to another results in a loss of energy due to the efficiency of the conversion. Eliminating conversions typically eliminates this loss and ultimately improves performance. Keeping the “Inherently Superior” paradigm shift in mind - since EVs power source is comprised in part or in whole from DC batteries - we should question whether PV, which generates DC electricity, demonstrate an advantage in charging DC batteries over charging them from an AC source, which would require conversion. Additionally, AC power is generally sourced from a grid that has extensive infrastructure to distribute the power to the final destination, but is not available in any location. PV DC power, however, can be generated virtually anywhere sunlight can be captured on the surface of its modules. This allows PV to be constructed at the final destination dramatically reducing grid infrastructure requirements while potentially leveraging conversion efficiency.

For EV’s, U.S. industry and society continues to pursue light duty vehicles. This market sector has unique capability and usability challenges beyond the cost and environmental benefits addressed by current product offerings and available incentive programs. There is no shortage of individuals and organizations determined to achieve laudable success as it relates to their fossil fuel competition for this market sector. However, when it comes to capability and usability, the solution remains elusive as capability, range, and extreme climate operations remain the focal point of development. Progress to resolve this concern is consistent, but the “tipping point” has not been reached. More importantly are the usability requirements of this specific market sector the most significant of which being refueling (charge availability and duration).

The public and private sectors have been aggressively attempting to overcome this critical obstacle. Because the viable existence of readily available EV charging locations is linked to a profitable level of demand translating into a quantity of EVs within said locations that far exceeds the current and the distant future levels of even the most optimistic projections, both the charging locations and the EVs that would use them fall short of supporting their symbiotic existence. While EV manufactures have pursued charging standards to reduce incompatibility issues that make the aforementioned “chicken or the egg” catch-22 even worse, that alone will have little impact on this insurmountable obstacle.

This inherently inferior quagmire for light duty vehicles by their users and the industry’s determination to pursue this market underscores a lack of interest in identifying inherently superior alternative markets; likely the result of focusing on quantity rather than quality. The very nature of battery charging is one of time regardless of technological advances. As these advances continue to improve upon charging limitations, chemistry and the laws of physics will always apply. These limitations inevitably set up a choice between benefits as it relates to capability, cost, usability and potentially environmental impact. While newer battery technology can be charged much faster as usability is being addressed, doing so will reduce its storage capacity and life cycle. This will lead to less capability during its life cycle and earlier replacement increasing the environmental impact of disposal while increasing the operating costs of the device powered by the battery. While existing efforts should be encouraged and continue uninterrupted, additional deliberation targeting inherently superior environments for EV and PV technologies is warranted and needed.

This hypothesis would be tested by creating a controlled environment where two DC sources of power would be utilized to charge a single battery. For the first DC source, it would utilize a charge controller specifically designed to complete its task using DC power. For the second DC source, it would first convert its DC electricity to 120 volt AC (120VAC) power typical of a standard outlet in a U.S. home. The 120 volt AC power would be converted back to a DC voltage appropriate for charging the battery. For each of these charge circuits, measurements of the voltage and amps of current flow at the DC source and target battery would be collected at a rate of 100 hertz. Utilizing Ohm’s Law (Pwatts = Iamps x Evolts), the common measurement of electrical power, watts would be calculated for each of the data points identified. This unit of measure provides a basis to compare the power generated and delivered in real-time while the test system is energized.

Originally, two identical make and model photovoltaic solar modules were to be used as the DC power sources. Initial testing found that these PV modules were incapable of producing the inrush current required to properly energize the 120VAC inverter equipment. Since watts of power provided by each source was being calculated using real-time measurements, voltage differentials of the sources would not degrade the integrity of the research. Subsequently, two DC batteries of the same make and model as the destination charging battery were wired in series to produce the 24VDC required by the 120VAC inverter. This resulted in the following test configuration: one DC source consisting of the two identical PV modules wired in series powering a solar charge controller, which in turn was connected to the destination battery and a second DC source of batteries, as previously described, connected to the 120VAC inverter, which in turn powered a 120VAC battery charger connect to the same destination battery. To further balance the factors of the two charging systems and the data ultimately collected for their comparison, the circuit design and components (wiring gauge, length, connections, data collection taps, etc) were identical with the exception of the conversion components of the second system. As a result, differentials in the data will be representative of performance efficiencies of the conversion designs.

Validation of the test system was completed on March 10, 2022. Data collection began on March 11th and continued through March 19th during solar hours. Additional collection was conducted on System 1 with a maximum output configuration to observe its full spectrum efficiency from complete darkness to the maximum irradiation of solar noon in lieu of configurations matching System 2 output. The following charts are representative of high and low power output operating modes of System 2 with System 1 configured to approximate the same charge current to the destination battery. These results remained consistent throughout the System 1 vs. System 2 contrast testing of March 11th through the 19th.

As it relates to PV power generation, it should be noted PV performance is highly dependent upon its operating location. These results collected in Arizona are indicative of and would be consistent with, the U.S. Sunbelt and may not hold true for systems operating in other environments. While the results identify an inherently superior performance advantage of a renewable energy, specifically PV charging batteries, there is a much greater context to understanding the current dichotomy in the propagation of these technologies throughout the U.S. Not within the scope of this investigation is the cost of a System 1 approach as compared to a System 2 approach. It stands to reason the reduced distribution and component design infrastructure of System 1 is likely less than a System 2 style deployment. Therefore, the likelihood that investment savings also exist for a System 1 approach may as well be significant. Focusing on an inclusive approach to improving the performance of renewables in their respective markets, this research identifies a framework to drive additional considerations from a different perspective - economics. Given the extensive environmental and incentive promotion as contrasted by market penetration in the U.S., hurdles clearly remain for these technologies and the probability economical performance is one of them is quite high.

The concept of evaluating the economical performance of renewable generation, distribution, and consumption is not new, but looking for the inherently superior opportunities to leverage their advantages might require renewed interest. Technology is and has been transforming life in the U.S. as well as around the world at an unfathomable pace, which sometimes leads to its own obsolescence just as rapidly. This may be applicable to current DC and AC grid designs. At the 1893 Chicago World’s Fair, Tesla won the world’s imagination when he illuminated the night with his AC electrical design of the Columbian Exposition ultimately winning the battle with Thomas Edison’s DC designs for the core construct of today’s electrical grid. At the time, the pursuit of AC systems was easily justified as it was far superior when it came to the biggest challenge of the era, scalable long distance transmission of significant power. Today, the playing field has changed dramatically with the advent of semiconductors which predominantly operate on DC power exclusively. EVs similarly work best utilizing DC power as do satellites, which operate in an environment where AC is difficult at best to generate or store. DC domains and the need to energize them economically are growing in kind creating opportunities for inherently superior deployments of genetically related DC energy applications like PV.

To illustrate the starting point of this shift in perspective, consider Amazon’s largest warehouse, “where you’ll find more robots than people”. The 10,000 robots, which outnumber the 1000 humans of the facility’s employment roster, put on “an electromechanical ballet” moving intricately through the facility and adjacent to one another dutifully maintaining the proper flow of inventory passing through the five-story plant encompassing the square area of 17 football fields hour after hour hardly making a sound. Facilities like these have prodigious battery charging systems and are therefore prime targets of opportunity for inherently superior PV battery charging deployments. Operations of this nature must locate where resources needed to fulfill their objectives are readily available, which includes electrical power. Utilizing PV could potentially enhance the profit equation by providing additional flexibility when selecting real estate for such an enterprise. These concepts demonstrate technology being deployed in a context where it naturally integrates with its user’s needs and expectations, which in turn, should improve acceptance and adoption.