The demand for portable generators is on the rise. In the industrial category, portable generators can be used in construction and drilling, and at mining sites where uninterrupted electric power is needed but the grid is not accessible—particularly in the Middle East, Africa, and Latin America, despite the fact that some countries and regions have imposed strict regulations on any equipment that contributes to global emissions levels. Because portable generators emit toxins, demand has been tempered amid worldwide concern for environmental protection.
Nevertheless, the residential market isn’t the only one seeking portable power. While the residential sector is predicted to account for nearly three-fifths of the revenue share, the commercial sector is expected to generate $40 million in revenue from 2017–2022.
According to a report by SBWire in July 2018, the global market has been growing due to increasing demand from residential, industrial, and commercial entities, with demand significantly heightened in the Asia Pacific region, which claimed the major share of the market in 2016.
According to Transparency Market Research, a global marketing intelligence company, North America was a close second, primarily because of demand due to natural disasters such as hurricanes, which disrupt the grid. Power outages—often caused by extreme weather and increased demand for uninterrupted power—have driven the demand for portable generators.
Power ratings are divided by “up to 5 kW,” “between 5 kW and 10 kW,” “between 10 kW and 15 kW”—which accounts for the major market share for residential and commercial purposes—and “above 15 kW,” which is a growing sector of the market due to increasing use at construction and mining sites, according to Digital Journal.
Most generators are fueled by diesel or gasoline, although bi-fuel and tri-fuel generators are now being produced. Gasoline is the most prevalent type of generator because it’s a readily available fuel that enables quick starting of the engine and it is compatible with smaller engines.
A new fuel has emerged: solar power. Woodland Energy produces HUBERT, Home Utilities and Boating Electrical Rechargeable Transporter, which obtains electrical current from solar power. Calling it the “only true microgrid,” Woodward Johnson, president, says the HUBERT, a source of rollable, moveable solar power, can provide the simultaneous production of alternating current (electricity from the wall) and direct current (electricity from a specialized, sealed battery).
“Most generators run on gas or propane,” observes Johnson. “Both are fossil fuels. Shale is the next big thing. But you need to maintain them, and it’s hard to find a mechanic.” They also must be properly vented and emit odors.
Conversely, solar panels are relatively inexpensive, Johnson says, and the generator can fit in a garage or basement. “The HUBERT generator must be kept inside, out of the weather. The plastic cover is not designed to be left outside 24/7.” The generator is charged by solar panels outside.
The HUBERT produces no exhaust and rolls fairly easily. Approximately 4 feet high by 2 feet wide and weighing 250 pounds, Johnson says it is “light, portable, and quiet, with big tires that make it easy to roll.”
The big questions are how long it will run and how much power it can produce. Johnson reports that it can produce 3,000 watts AC at 120 volts or 200 watts at 12 volts. “It won’t produce peak power for long without being charged at the same time. You must use less power or figure out how to keep them charged.” Personally, he says he never turns off the one in his home, on which he charges all his devices.
Similarly, most of Woodland Energy’s customers are homeowners, although Johnson says airports also use the generators to allow customers to plug in their cell phones. For homeowners, making their own power simply and cheaply is key, he says. “Low-voltage energy saving equipment is the thing now.”
“There’s not much new in solar,” states Johnson. “If there’s any development, it’s improvements in solar panels: how they’re made, what they’re made of, where they’re coming from.”
On the contrary, researchers at the University of British Columbia have discovered an inexpensive, sustainable way to build a solar cell using bacteria that convert light to energy. This cell, called biogenic because it consists of living organisms, works as efficiently in low light as in bright light. It’s believed that it could eventually become as efficient as synthetic cells used in conventional solar panels.
Solar cells convert light into electrical current. Previous efforts to build biogenic solar cells extracted the natural dye that bacteria use for photosynthesis; however, extraction requires the use of toxic solvents and energy—and the sensitivity of the dyes to the light results in significant degradation before they are introduced into the solar cell. Furthermore, it’s a costly and complex process.
The researchers decided to leave the dye in the bacteria and genetically engineer E. coli to produce large amounts of lycopene—a phytochemical that gives tomatoes and other red fruits their color and is effective at harvesting light for conversion to energy. They coated the bacteria with a mineral that could act as a semiconductor and applied it to a glass surface. With the coated glass acting as an anode at one end of the cell, they generated a current density of 0.686 milliamps per square centimeter, according to the journal Small.
This process addresses the limitations of the previous method and makes solar cell manufacturing more affordable. It’s a different process, which produces a more powerful current. Hybrid materials can be manufactured economically and sustainably, and are believed to be able to perform at efficiency levels comparable to conventional solar cells. They also contribute to reduced costs.
However, the bacteria die during the process. If a method of keeping them alive can be found, they could produce the dye indefinitely. Thus, biogenic solar cells are considered a first-generation prototype not yet ready to complement inorganic solar cell technology.
Solar energy is considered a leading candidate for de-carbonization in the energy sector. Research goals for solar energy include: increasing the efficiency of conversion to electricity, reducing costs, storing energy more efficiently at lower cost, and finding new ways to convert solar energy to electricity.
Currently, the two predominant methods of converting solar energy to electricity are photovoltaics and solar thermal power, known as CSP. One area of research in PV is to discover more forms of materials that are abundant and do not become hazardous waste at the end of their life—such as dye-sensitized solar cells, polymer solar cells, and perovskite solar cells.
CSP is more expensive than PV, but because it uses the same thermal power conversion as conventional thermal power, it can be easily integrated with existing infrastructure. It also uses thermal energy storage at about one-tenth the cost of battery storage.
Research continues in other areas, including desalination and refrigeration, which incorporate combined cycles. Research also continues in an effort to improve and reduce the cost of battery storage and thermal energy storage.
Johnson expresses some concern about the political climate’s impact on investment and involvement with the solar industry, but insists that it is the fuel of the future. “We must make our own electricity—for crises, if nothing else. Our generators cost $6,000 and don’t wear out. They’re quiet, and if you keep them clean and keep the battery charged, you’ll have plenty of power when you need it, whether you need power at a job site, in the woods, for daily use at home, or just for backup power.”