Automotive chemical manufacturer Prestone is currently developing a low-conductivity electric vehicle (EV) coolant that scientists hope can increase EV efficiency.
While ethylene glycol is used in both gas vehicles and EVs, including Teslas, Prestone has increased its research and development budget for learning about less conductive cooling fluids over the past year, as detailed in a report from Automotive News on Friday. Prestone EV Director Tom Corrigan says that that won’t be the case in the future, as the company seeks to develop its own.
“Essentially, EVs are borrowing the internal combustion engine fluid,” Corrigan said. “We are going to see a shift in that in the next one to two years.”
The company has been testing its low-conductivity EV coolants in Ford Mustang Mach-E vehicles at its tech center in Danbury, Connecticut, in recent months. While initial offerings are roughly two years away and will still include ethylene glycol bases, Corrigan also says that petroleum-based dielectric coolants could replace the chemistry in future years.
Coolant types may also be dependent on battery chemistries, with lithium-iron phosphate (LFP), solid-state, and nickel manganese cobalt batteries likely all requiring different coolant makeups. Tesla writes on its website that its cooling systems currently use a phosphate and nitrate-free ethylene glycol-based coolant.
Ethylene glycol can ionize over time when it interacts with metals, plastics, and other necessary engine materials. As the coolant gains electrons, the overall efficiency of a battery-electric vehicle (BEV) is decreased. In addition, the coolant chemistry is expected to shift because of safety, as a BEV-friendly replacement for the corrosion inhibitors used in ICE coolants.
“Those ionize in the fluid and carry an electrical charge. If you have an issue where high-conductivity coolant contacts high-voltage electronics or the battery, it can lead to fire,” Corrigan explains. “So what we are working on is low-conductivity coolant.”
Scientists evaluate the electrical conductivity of coolants using a unit called microsiemens, which measures the conductivity per centimeter. In gas cars, experts expect to see between 3,000 and 5,000 microsiemens per centimeter, considered highly conductive, though it doesn’t negatively interact with gas vehicles in the same way it does for BEVs.
Instead, BEV makers are asking Prestone to develop a coolant with just 100 microsiemens per centimeter, while other fuel cell vehicles may require coolant conductivity levels of just 0.5 to 1.5 microsiemens, according to Corrigan.
“Every bit of increased conductivity is a loss of efficiency in the fuel cell. You’ve got to make the fluid very pure,” he notes.
Along with adding to the company’s R&D budget, Prestone added an additional five scientists and engineers in the department developing coolants for BEVs and fuel cells.
“We see where the future is going with EV coolants, and we want to be ready when the manufacturers are ready,” Corrigan says.
RELATED:
StoreDot closes in on U.S. market entry with launch of R&D campus in California
What are your thoughts? Let me know at zach@teslarati.com, find me on X at @zacharyvisconti, or send us tips at tips@teslarati.com.
News
Tesla Roadster is available for order once again following brief hold
Tesla has reopened reservations for its long-delayed next-generation Roadster, asking buyers for a $50,000 deposit just days before an October 1 reveal event in Waco, Texas. The move revives a reservation process first launched in 2017 and later paused when Tesla pulled pricing from its website in 2021.
The reservation page requires an immediate $5,000 credit-card payment, described as fully refundable, followed by a $45,000 wire transfer due within 10 days, which is identical to what was expected previously. Reservations are not considered final until the wire clears.
The structure matches the 2017 terms Tesla used when it first collected deposits after unveiling a prototype. Tesla has not published a confirmed retail price or production start date on the order page.
Go buy a Roadster pic.twitter.com/n7rhouAmIS
— TESLARATI (@Teslarati) September 21, 2026
The October 1 event is scheduled in Waco, about 90 minutes north of Tesla’s Austin headquarters and near SpaceX’s McGregor rocket test site. Tesla sent invitations to existing reservation holders and posted a “Go for launch” teaser on September 12.
The Federal Aviation Administration (FAA) established a temporary flight restriction over the McGregor area from September 18 through October 2, consistent with plans for a demonstration involving SpaceX-designed cold-gas thrusters. Elon Musk has previously described the optional package as enabling extreme acceleration or brief hovering. Tesla has said the event will include pricing, specifications, and production targets.
The second-generation Roadster was first shown in November 2017 during Tesla’s Semi launch. Musk promised production in 2020, with claimed performance of 0-60 mph in 1.9 seconds, more than 250 mph top speed, and roughly 620 miles of range.
Those targets have slipped repeatedly.
Tesla later pointed to 2022, 2023, 2024, and 2025-2026 before indicating production would not begin until 2027 or 2028 at Gigafactory Texas. Design work has continued, with reports of a sharper, Cybertruck-influenced look replacing the original curvy prototype.
Original reservation holders who paid $50,000 in 2017, or $250,000 for the Founders Series, have waited nearly nine years without a production car. Some high-profile customers canceled. Tesla’s decision to reopen orders now, after previously shutting them down, tests whether new buyers will commit substantial funds before seeing a finalized production vehicle. The October 1 event is intended to answer remaining questions about what those buyers will actually receive and when.
News
Tesla Full Self-Driving expands to another European country
Tesla’s Full Self-Driving (Supervised) is heading to Czechia after the Czech Ministry of Transport recognised the Dutch RDW’s provisional type approval, making the country the seventh EU member state to clear the system for public roads. Tesla Europe announced on 21 September 2026 that “FSD Supervised is now approved in Czechia” and that rollout “will begin soon.”
The decision marks a notable reversal. Earlier in 2026, Prague had declined to automatically recognise the Netherlands’ April approval, citing concerns over speed-limit compliance, traffic-sign recognition and driver-attention monitoring, and arguing that a coordinated EU approach was preferable. Officials said months of expert review, talks with Tesla and other member states, and real-world data from countries already using the system resolved those issues.
🚨 Tesla FSD heading to Czechia 🇨🇿 pic.twitter.com/mkzlM9QjrB
— TESLARATI (@Teslarati) September 21, 2026
“Safety remains the top priority,” the ministry stated.
FSD Supervised remains a Level 2 driver-assistance system: the driver must stay engaged and is legally responsible. Eligible vehicles need AI4, the company’s most up-to-date hardware version. Tesla is expected to push the feature over the air in the coming days, following the pattern seen after earlier national approvals.
Europe’s rollout began when Dutch regulator RDW issued a provisional EU type approval on 10 April 2026 after extensive testing. Mutual recognition then produced a rapid cascade: Lithuania (20 May), Estonia (29 May), Denmark (9 June), Belgium (10 June) and Slovenia (7 September). Czechia now completes that list of seven.
The approvals cover only a modest share of the EU population, but they add political weight ahead of a 6 October vote by the Technical Committee on Motor Vehicles. A qualified majority, at least 15 of 27 member states representing 65 percent of the EU population, could open the remaining markets, including large ones such as Germany, France, Italy and Spain that have so far preferred to wait for a bloc-wide decision.
For Czech Tesla owners, the immediate prize is access to the same supervised highway and city driving already available in the other six countries. For Tesla, each new market generates additional European driving data and strengthens the case that FSD Supervised can operate safely under the continent’s varied road rules. The Czech approval is therefore both a local milestone and another incremental step toward a wider European launch.
News
Tesla Roadster event requires restricted airspace, and the FAA obliges
The Federal Aviation Administration (FAA) has established a Temporary Flight Restriction over SpaceX’s McGregor, Texas, rocket development and test facility, a move widely viewed as preparation for Tesla’s October 1 Roadster reveal. The restriction took effect September 18 and runs through October 2.
NOTAM FDC 6/3825 covers a 1.5-nautical-mile radius around the site near Waco and extends from the surface to 10,000 feet above ground level. The FAA cited hazards under 14 CFR 91.137(a)(3) and barred aircraft and drones from the zone. Tesla’s invitation to reservation holders already placed the event in Waco, about 20 minutes from McGregor, making the timing and location more than coincidental.
A TFR has appeared around SpaceX’s McGregor Testing Site up to 10,000ft and runs through until the 2nd of October 👀 pic.twitter.com/rcZ4p4JkLm
— Niall Anderson (@INiallAnderson) September 18, 2026
What stands out is the altitude. Typical recent TFRs at McGregor for engine static fires and component tests have used far lower ceilings, often around 2,000 feet. Raising the limit to 10,000 feet is unusually high even compared with some Starbase restrictions and signals operations that go beyond a standard ground-level engine test.
That extra airspace has fueled speculation about the long-promised SpaceX Package for the Roadster. Elon Musk has described cold-gas thrusters that could deliver sub-one-second 0-60 times and, more dramatically, brief lift-off. Reports earlier this year indicated Tesla planned a remote-controlled demonstration at McGregor in which the car would leave the ground with no one inside; spectators kept hundreds of yards away because of the noise.
The 10,000-foot envelope would give operators a large safety buffer even if the vehicle only hovers a short distance.
Tesla has not confirmed a flight demo. The company has only used the phrase “Go for launch” and posted a teaser image of the car on what looks like a launch pad. The TFR itself mentions only hazards. Still, closing airspace this high and this close to the reveal date strongly suggests the event will include more than a static display.
Whether the Roadster actually hovers on October 1 remains to be seen. What is certain is that the FAA has cleared a large vertical slice of Texas sky for whatever Tesla and SpaceX intend to show. Reservation holders heading to Waco will be among the first to find out if the car can do more than drive.