AERREVA  H-Series

Upcoming Energy Crunch

Sources of Energy
All-electric vehicles (EVs) run solely on electricity, which is produced in the United States mainly from fossil fuels (60.4%) and nuclear energy (18.2%). Although EVs have no tailpipe emissions, using electricity generated by these primary energy sources creates emissions elsewhere, in addition is not efficient, or sustainable.

Fossil Fuels Required for EV Charging
Taking into account power plant efficiency (around 33%) and power transfer losses to the EV battery, fully charging a 100 kWh EV battery requires burning around 142.5 pounds of coal or 927.5 cubic feet of natural gas thereby producing 295 pounds of CO2 for coal, and 112 pounds for gas, along with other pollutants. This calculation does not include the energy used in the extraction, production, and transportation of these fuel sources.

Issues with Nuclear Energy
Nuclear energy is often portrayed as clean, emission-free, and sustainable. However, producing nuclear fuel involves significant energy input for mining, milling, conversion, enrichment, and fuel fabrication, which produces emissions, toxic chemicals, and radioactive waste. Other challenges include managing high-level nuclear waste for over 10,000 years, and decommissioning a power plant, which is complex and take over 30 years to complete. When considering all factors, including environmental cleanup from natural and man-made disasters, the Energy Return on Investment (EROI) for nuclear energy may end up being miniscule, potentially making it an energy sink and not a viable source of energy.

Renewables and Capacity Factors
Solar and wind farms make up approximately 3.9% and 10.2% of total electricity production in the US, respectively. Because these energy sources are dependent on weather conditions, energy production is intermittent and will also fluctuate daily, with annual capacity factors of 28% and 35%, respectively. Load-following power plants (mostly fossil fueled) are therefore needed to deliver consistent electricity to consumers. Power plants that ramp up and down are less efficient and produce more emissions. As far as hydropower, it contributes around 6.2% of total electricity production in the US, with a capacity factor of around 40%, due to fluctuating water availability.

Declining Energy Sources
Globally, the projected reserves for oil, natural gas, coal, and uranium are expected to last for another 57, 49, 139, and 90 years, respectively. In the US, the estimated longevity is 5 years for oil, 86 years for natural gas, and 422 years for coal, based on current consumption levels. Source: https://www.eia.gov. In regards to uranium, the US imports almost all of its uranium from other countries, which have higher grades of uranium ore. When the extraction of oil becomes too energy-intensive, i.e. the EROI has declined to low single digits, the automotive industry will then shift from predominantly gasoline-powered vehicles to all-electric vehicles, with most of their power then derived from natural gas, and thereby deplete natural gas reserves faster. Once natural gas extraction becomes too energy-intensive, coal will likely become the dominant source of energy for generating electricity.

No Easy Long Term Solutions
The national power grid is already facing strain, especially during the summer months when air conditioning systems are used extensively. Adding tens of millions of electric vehicles would further strain the grid, leading to more outages, and faster depletion of our energy resources. For more information on the electrical grid, primary energy sources, and electric vehicle efficiency, please visit our Electrical Grid page.

Sustainable Transportation Solution – AERREVA SC-EV concepts

Introducing the AERREVA self-charging all-electric vehicle concepts (SC-EV), that provide for a sustainable transportation solution. The design concepts focus on high efficiency and high solar and wind energy production. The solar-wind hybrid generating system includes a hidden extendable solar panel array subsystem mounted on a sun tracking system. Tracking solar panels produce much more energy than stationary panels, especially in the northern hemisphere. The wind tracking horizontal axis wind turbine (HAWT) subsystem features a telescoping tower and extendable blades that can produce much more wind energy when the blades are fully extended. Doubling the size of a rotor diameter quadruples the HAWT’s energy output. When parked, the subsystems can be activated automatically when favorable weather conditions are detected or stowed away during adverse weather, such as hail, extreme winds, or icing conditions. Surplus energy generated daily can be used to supply electricity to a home, and through net metering, reduce a home’s utility bill with renewable energy credits. Depending on electricity rates and weather conditions, home credits can range from around $100 to $500 per month.

While small wind turbines can’t compete with the generating capacity of a large turbine, there are advantages to small turbines. Small turbines can be directly connected to the battery charger, eliminating transmission losses due to the long-distance between consumers and wind farms. Small turbines are also easier and cheaper to maintain. No need to travel long distances or climb tall towers. The cost of replacing a single large wind turbine blade can be as high as $300,000, and the gearbox can cost over $500,000. Smaller turbines can be placed much closer together, unlike large turbines that require up to 80 acres in order to avoid interference from neighboring turbines. Smaller turbines also operate at a lower blade tip speed (around 100 mph versus 180 mph for large turbines), reducing the likelihood of leading edge erosion, blade furniture detachment, delamination, or blade structural failure due to collisions with birds, lightning strikes, rainfall, salt, dust, insects, and other airborne particulates.

Features of the AERREVA SC-EV concepts include a centerline battery compartment and tandem seating that provide increased stability, handling, and protection for both passengers and batteries. The batteries, housed in a slidable tray, can be removed from the back end. The battery compartment also serves as a seat and chassis support. The battery tray can accommodate different types of batteries, such as lithium-ion, absorbent glass mat, or even lead-acid. The patent-pending AERREVA H-Series offers various models designed for different operating environments. Energy production estimates are available on the solar and wind energy pages. A new V-Series, configured with a different type of wind turbine that’s suited for areas with shifting winds is also in the works, in addition to other series.

The H-Series is a combination of various wind turbines and solar panel configurations. The HAWT is extendable and can be paired with either a tiltable (T) or non-tiltable (S) solar array subsystem. The number of blades on the turbine rotor can be varied to optimize performance in different wind conditions. More blades generate more torque in low wind conditions, while fewer blades, such as the 2nd and 3rd three-blade versions, are better for high wind conditions. Even blade configurations can be neatly stowed in the aft section of the vehicle, while the 3-blade model (3H) with the largest rotor diameter can be stowed as shown below. A tracking solar array is best suited for areas with low sun angles, while a non-tilting solar array is better suited for areas with high amounts of sunlight.

The four different configurations include:
TH – Tracking solar array with an HAWT fitted with an even number of blades.
SH – Extendable solar array (non-tracking) with an HAWT.
T3H – Tracking solar array with a three-blade HAWT.
S3H – Extendable solar array (non-tracking) with a three-blade HAWT.

---

H-Series features
The vehicle has a cabin positioned at the center line to improve visibility, handling, and safety. It also has a lightweight design and a small frontal surface area for higher efficiency. The battery pack at the center line is removable. Other features include large bypass air channels for better aerodynamics, a horizontal axis wind turbine subsystem that can be extended, a top-side solar array for charging while on the go, and a retractable solar array subsystem. The vehicle also has sloped top side decks to allow rainwater to run off, an extendable anemometer for measuring wind speed and direction, a large cabin door for easy entry and exit, and removable overhead canopies for open-air driving or emergency exit. The vehicle has a radiator to cool the battery pack, dampers to cool solar cells and increase efficiency, all-around crumple zones to protect occupants, and easily removable seats. Its wide body offers stability and enables the accommodation of large solar and wind turbine subsystems. Moreover, most suspension components are protected from the airstream. The vehicle is equipped with side and rear view cameras and has a spare tire that is stored in the outer wall compartment.

Battery Options
The battery pack, located centerline under the seats, is protected by belly panels and chassis rails. It can hold various types of batteries, including Lithium-ion and Absorbent Glass Mat. The estimated range is 1,885 km (1,171 miles) for Lithium-ion and 311 km (193 miles) for AGM. Larger battery packs increase range but also add weight, which increases rolling resistance. Lead acid batteries are better suited to subzero conditions, but have less than a quarter of the Watt Hours per Kilogram energy of Li-Ion batteries.

---

Generating Solar Energy

When the Sun sensor detects favorable conditions, it activates the solar array subsystem while parked.

Solar Array Capacity
The energy produced by solar cells depends on various factors such as the Sun’s strength and angle, air quality, and the efficiency of the solar cells. At sea level, the Sun’s energy density is approximately 1,000 Watts per square meter. Solar cells with a 22% efficiency can produce up to 220 watts per square meter. When all the solar arrays are combined and positioned horizontally, they can generate 1,512 watts, or 7.56 kWh in one day, which can power a vehicle for daily trips of around 60 miles. Mileage estimates are based on an energy consumption of around 6.714 kilowatts per hour (kWh) or 122 watt hours per mile at 55 mph. However, tracking can more than double energy production, especially in winter months when the Sun’s angle is low. Production estimates are based on an average of 5 kWh per square meter of solar energy as shown by solar energy maps from the U.S. DOE, National Renewable Energy Laboratory. The amount of solar energy varies based on the region, with Southwestern states having more energy per day than Northeast parts of the U.S.

---

Generating Wind Energy

The vehicle’s wind turbine subsystem features a telescoping mast and rotor with extendable blades that can be stored in the rear section. An ultrasonic wind anemometer detects wind speed, duration, and direction to activate the turbine when favorable winds are detected when the vehicle is parked. The horizontal-axis wind turbine (HAWT) can have either an even number of blades (2, 4, 6) or a 3-blade version, which is the largest in the H-Series and produces the highest power output. Turbines with more blades provide more torque in low winds, while fewer blades increase the flow speed and are better suited for high wind conditions. When the vehicle is parked, the various HAWT subsystems can be activated when favorable conditions are detected.

3 Blade HAWT

6 Blade HAWT

The other blade configurations, a 4-blade, are not currently displayed.

Rotor Diameter	Wind Speed	Wind Speed
6 feet	15 mph -> 130 watts	30 mph -> 1,169 watts
9 feet	15 mph -> 294 watts	30 mph -> 2,640 watts
11 feet	15 mph -> 441 watts	30 mph -> 3,950 watts

Wind speeds of 20 mph or more in areas like the Midwest and Great Plains can generate enough energy in 24 hours to power a vehicle for 500 miles, and more with stronger winds. Mileage estimates are based on energy consumption of about 6.714 kWh or 122 watt hours per mile at 55 mph.

Solar Energy + Wind Energy
Over 30 days, the solar panels and wind turbine can produce a total of 3,070 kWh of energy. This amount of energy is capable of charging an 80 kWh battery pack 39 times. For additional examples of renewable energy production, please visit our solar and wind energy pages.

---

Energy is Money
Net billing or net metering with AERREVA electric vehicles can help lower the electricity bills of a household. Electricity rates vary from state to state, with Hawaii having one of the highest rates at an average of 46.52 cents per kilowatt-hour (kWh), while Nebraska charges around 10.58 cents per kWh. By combining the energy output from solar and wind sources, it’s possible to generate approximately 1,068 kWh of energy every month, with renewable energy credits amounting to around $113.00 in Nebraska and $496.83 in Hawaii. As the demand for energy increases and the shift to more expensive energy sources takes place, electricity prices are projected to rise.

Nationwide Wind Energy Potential
Small wind turbines can produce significant energy. One million turbines generating 28 million kWh can power almost a million homes in 20 mph winds for 24 hours. At 30 mph winds, the same number of turbines could power four million homes. Even with 15 mph winds, 10 million kWh could be produced daily, enough to power half a million homes.

(28 kWh x 1,000,000 = 28,000,000 kWh) (20 mph winds/24 hours).
(94 kWh x 1,000,000 = 94,000,000 kWh) (30 mph winds/24 hours).
10,000,000 kWh (10 mph winds/24 hours).

Energy Production Estimates
The estimates for solar and wind energy production do not account for the fact that an average car is parked around 95% of the time. Additionally, the DC to AC conversion efficiency has not been considered.

Development Stage
AERREVA H-Series EVs are currently in the early stages of development, from conceptual drawings to patent applications and prototypes. The next step is to build a functioning prototype. The vehicle and its wind and solar subsystems and methods are Patent Pending (Utility Patent Application) filed by DLA Piper LLP (US), a global company that provides intellectual property and patent services. They have been extremely helpful, providing information and guidance throughout the process.

Acknowledgments
The author acknowledges the National Aeronautics and Space Administration (NASA), the United States Environmental Protection Agency (EPA), the United States Department of Energy (DOE), the U.S. Energy Information Administration (EIA), and the National Renewable Energy Laboratory (NREL) for providing data.

Other AERREVA series
Currently in development are various AERREVA series and their variants. This includes a larger horizontal-axis wind turbine with a tower design, a larger solar array subsystem that can be attached to any variant, a new type of wind turbine that is more suitable for urban areas where wind direction changes frequently, and a wider cabin design for increased seating

LH – larger HAWT and tower.
LSP – larger solar array subsystem.
V Series – new type of wind turbine.
W Series – wider cabin.