Metals Tech

Many of us who are interested in electric vehicles and solar power have probably wondered if this form of clean electricity could be integrated into an EV somehow. In fact, for some years now, there have been a number of solar-powered car races conducted. However, these vehicles, though impressive in their engineering and abilities, do not meet consumer expectations for speed, comfort, safety, passenger capacity, and storage space.

In a word, they are impractical and not “there” yet in terms of what most of us would find acceptable or even desirable. Also, they could probably not be made street legal in their current incarnations. Finally, they simply have a very odd appearance resembling a narrow waffle with a bulbous area for the driver to see out of, for the single passenger versions. There is a cruiser class for some of these competitions and these vehicles can transport multiple passengers. However, the larger ones still are not road-worthy for normal driving conditions on city streets and are far too slow for freeways and highways.

Of available commercial vehicles, the Toyota Prius Prime in Japan has a rooftop solar power option, but it doesn’t generate that much electricity, perhaps enough to add about 3.8 miles of driving distance to the vehicle’s batteries when there is adequate sunlight.

There has been some speculation about what a small solar power system on the Karma Revero might be capable of, but a writer summarize the numbers he collected and emphasize how little the panel provided: “So, again, about a month. A month of non-stop solar charging, to get you a full battery, which Karma says will take you a whole 50 miles.”

Sono Motors has developed an EV called the Sion, which has more solar cells embedded into its body — about 81 square feet of its surface. It does meet basic consumer expectations in terms of the conventional form and finish, but the extra dimension of having some solar power is intriguing. The range per charge is about 155 miles, and the solar power system has been estimated to have the capacity to add approximately 18–19 miles of electricity per day in order to recharge the battery when there is adequate sunlight.

The fact that this startup accomplished what it did is impressive, and when Sono vehicles are operating in the consumer world, their very presence will turn some heads and demonstrate that such a technology is indeed possible. The amount of electricity the Sono EV rooftop solar power system will generate won’t be that much, but it is a step further than companies have gone before.

One problem with putting solar cells on cars is that there simply isn’t enough surface area. A small collection of solar cells can’t generate nearly enough electricity to function as a primary source.

Even if solar cells can eventually be made that have two times greater efficiency, solar cells on cars would still not generate enough electricity to be the main source. They will be helpful in situations where an EV is going to sit outdoors in sunshine where there are no chargers, but solar power on car bodies will play an auxiliary role for quite a long time to come — perhaps indefinitely.

Aside from simple limitations in efficiency and cost of solar panels, remember that cars often park in the shade, are often shaded by buildings even when they are in daylight, and can rather easily get into accidents — which could mean the destruction of highly valuable solar technology.

A more practical approach is to put solar panels on your roof or carport and charge your car there. The good news is, that’s what 28–42% of electric car drivers do, according to our research, or 32% according to more recent research. Collecting solar energy on stationary roofs and using that electricity to charge competitive electric cars makes a lot of sense, so let’s hope a lot more people go that route in the coming years … er, months … er, days.

Last month, many major airlines enacted a ban on “smart luggage” with non-removable lithium-ion batteries. However, according to Steph Korey, the CEO of luggage company Away, airlines have been prohibiting smart luggage even if it has a removable battery and should be allowed under the new policy.

In an internal email sent the Away team, Korey says there has been confusion with airlines as to which bags are and are not allowed. “Some airline employees have prohibited passengers from carrying on their carry-ons with the battery inside,” she writes. “Unfortunately, this isn’t just a few isolated incidents — over the past several weeks, we have heard from hundreds of customers regarding incidents where airline employees have made it clear they don’t understand their own airline’s policy.”

Per the new rules which went into effect on January 15th, all smart bags must have a removable battery. If the bag is being checked, the battery must be removed and carried on board by the passenger. If the bag is for carry-on, verbiage varies a little depending on the carrier. Delta’s website does not specifically address carry-on bags, but broadly says, “Smart bags with removable batteries will still be allowed if the battery can be removed on site and taken on board the aircraft with the customer.” American’s website clearly states regarding carry-on bags: “If the customer is able to take the bag into the cabin with them, the customer will be able to leave the battery installed.” Regardless of specifics, if the battery is removable, it should be allowed on board as a carry-on.

However, many passengers traveling with bags that have removable batteries have found that airline employees are unclear on the new rules, and many aren’t allowing them onboard at all.

The new restrictions were helmed by American Airlines and the International Air Transport Association in efforts to reduce the risk of fires caused by lithium-ion batteries. Hoverboards and Samsung’s Galaxy Note 7 were banned for the same reason.

While there are bound to be growing pains with any new policy change, poor enforcement of these rules could be a major detriment to the smart luggage market, dissuading people from purchasing one when most are still fine to use under the new policies. To be clear, as long as your smart bag has a removable battery, you can check it with the battery removed, and you should be able to bring it on board as a carry-on.

With coal mining becoming a thing-of-the-past, the world will be left with a lot of empty mine shafts. However, a group of entrepreneurs in the UK has come up with an idea that would breathe life back into coal mining communities.

The newly formed energy company, Gravitricity, has a patented technology to make old mine shafts generate energy using a giant weight system. Gravitricity has secured a £650,000 grant from Innovate UK, the government innovation agency to undertake the development of the sub-system design and deploying a 250kW concept demonstrator. The company aims to trial the first full-scale prototype in 2019 or 2020 at a disused mine in the UK.

The idea behind stored energy

As more and more electricity is generated from intermittent renewable energy sources, there is a growing need for technologies which can capture and store energy during periods of low demand and release it rapidly when required. Gravitricity looked at the problem and came up with an energy storage solution that uses the best characteristics of lithium batteries and pumped storage.

The company claims the technology is ideally suited to network-constrained users and operators, distribution networks and major power users, the technology operates in the 1MW to 20 MW power range and enables existing grid infrastructure to go further in a renewable energy world.

Pumped-storage hydroelectricity allows energy from intermittent sources (such as solar, wind) and other renewables, or excess electricity from continuous base-load sources (such as coal or nuclear) to be saved for periods of higher demand.

Many recently proposed projects avoid highly sensitive or scenic areas, and some, like the 2012 study by the European Renewable Energy Network propose to take advantage of “brownfield” locations such as disused mines.

Basically, Gravitricity’s patented technology uses a simple principal – What goes up must come down, or in this case, raising and lowering a heavy weight to store energy. In practice, it has similar advantages to pumped storage for networks up to 33kV, but without the need for a nearby mountain with a lake or loch at the top. And that is the good part of the plan.

Gravitricity’s technology and how it works

Gravitricity managing director Charlie Blair explained the system: “A cylindrical weight of up to 3000 tonnes is suspended in a deep shaft by a number of synthetic ropes each of which is engaged with a winch capable of lifting its share of the weight.” It appears that electrical power is absorbed or generated by simply lowering and raising the weight.

The weight is guided by a system of tensioned guide wires (patents applied for) to prevent it from swinging and damaging the shaft. The winch system can be accurately controlled through the electrical drives to keep the weight stable in the hole.

Blair said, “The winches become generators, producing either a large burst of electricity quickly, or releasing it more slowly depending on what is needed. When there is excess electricity, for example on a windy day, the weight is winched to the top of the shaft ready to generate power.”

“This weight can then be released when required, in less than a second, and the winches become generators, producing either a large burst of electricity quickly, or releasing it more slowly depending on what is needed, Blair adds.

The company claims the system has a work life of 50 years and is 80 to 90 percent efficient. And besides being versatile, it is also simple to operate and cost-effective when compared to lithium-ion batteries. Bottom line? All you need is a deep hole in the ground.

The California Public Utilities Commission has adopted a planning process to ensure the electric sector is on track to help the state meet its 2030 greenhouse gas reduction target, at least cost, while maintaining electric service reliability.

The decision establishes a two-year integrated resource planning cycle for electricity providers. The first year of the cycle is designed to evaluate the appropriate emission planning targets for the electric sector, and to identify the optimal mix of system-wide resources capable of meeting these targets. The second year is designed to consider the suite of actions each electricity provider proposes to take.

The CPUC adopted a statewide electric sector carbon reduction target of 42 MMT by 2030, which represents a 50 percent reduction in electric sector carbon emissions from 2015 levels and a 61 percent reduction from 1990 levels.

In order to provide a general planning direction to the electric sector, the CPUC adopted a portfolio of energy resources including 10,200 MW of new renewable energy resources and 2,000 MW of new battery storage resources by 2030. The commission endorses a steady approach to ongoing procurement of zero-carbon resources over the planning horizon to 2030, which subjects consumers to less financial risk.

“California isn’t just sitting back watching our successful renewable energy programs continue to grow. This decision establishes an aggressive greenhouse gas emissions reduction target and implements an entirely new planning framework for the electric sector that focuses electricity providers on finding optimal strategies to reduce carbon emissions at least cost while maintaining grid reliability,” said Commissioner Liane M. Randolph, who is assigned to the proceeding.

“The integrated resource planning framework represents a great step forward in optimizing our procurement to reduce greenhouse gases and costs,” said Commissioner Carla J. Peterman. “I look forward to further integrating our electric vehicles and energy efficiency investments into the modeling.”

“This decision puts into practice important environmental justice mandates, including that utilities must detail their plans for reducing localized air pollutants in disadvantaged communities, and spell out how they will give preferences for procuring non-fossil resources in these communities,” said Commissioner Clifford Rechtschaffen.

The proposal adopted is the culmination of two years of staff work that included 13 webinars, eight workshops, 11 staff proposals, and review of thousands of pages of public comments from more than 50 parties.