One prominent alternative fuel manufacturer, however, has been more reticent. Tesla Motors (TSLA), the Silicon Valley maker of battery-powered electric cars, is not revealing any plans about what it plans to display at the show and has not requested a slot at the show for a formal news conference.

Tesla’s silence has created a news vacuum that bloggers have been anxious to fill with speculation about the company and its plans for future models. “Tesla Model X To Be Unveiled At 2015 NAIAS?” asked the website Inside EVs, while EV World guessed “40K Tesla Electric Car Debut Possible at 2015 NAIAS.”

This isn’t idle car talk. Both Model X and Model III are critical to Tesla’s future success and its ability to support its stock price. Goldman Sachs, for instance, has warned that if a production version of the Model X SUV doesn’t debut at the show, it will consider the project, which was due to go on sale at the end of year, delayed once again, denting revenue projections. As for the Model III, it has been pitched as an affordable $40,000 car aimed at the mainstream market and thus high volume. That makes it the linchpin of CEO Elon Musk’s ambitious growth plans.

Seeing an opening, short sellers of Tesla stock are taking advantage. They assume the worst and figure Tesla doesn’t want to expose itself at the show to any embarrassing questions. “I interpret this to mean the December quarter is extremely back-end loaded and therefore likely on the weak side,” wrote Anton Wahlman on Seeking Alpha. He predicted that if Tesla does miss the quarter and report lower than expected sales, “the stock would likely plummet.”

The stock has already taken quite a hit. In one month’s time, Tesla’s stock price has collapsed from $259 to the low-$200 range. Oddly, lower gas prices aren’t seen as a factor, since buyers of the $80,000 Model S are hardly penny pinchers. Bargain hunters aren’t nosing around yet. The company still operates at a loss and is selling for 70 times forecast 2015 earnings.

At the same time, Tesla is getting pressure from competitors who are upping their game. Even the struggling Chevy Volt (GM) gets an upgrade for its 2016 model. CEO Mary Barra is promising that it will be more efficient and go further faster than the current model. The EV range, which grew from 35 to 38 miles in 2013, is likely to be pushed to about 40 miles.

Far more consequential is the renewed interest among automakers in fuel cells as an alternative to battery electric power and as a successor to the internal combustion engine. And among the manufacturers rushing to bring fuel cell cars to market, the 800-pound gorilla in the room is Toyota.

Along with Honda, Toyota has long been a leader in alternative fuel technologies, beginning with its introduction of the gas-electric hybrid Prius. Now 20 years old, the Prius has been so successful that several variants have been created and it’s being treated as a sub-brand within Toyota. In covering the auto industry for 38 years, one of my rules has become “Never bet against Toyota.” And lately, Toyota has been putting its money down against Tesla.

Here’s the history of what has transpired: Anxious to get a look at Tesla’s EV technology, Toyota acquired a 3% stake in the company in 2010 and signed a $100 million joint development deal in 2011 for an electric-powered version of the RAV4. At the time, it hinted there could be additional projects with Tesla. But earlier this year, Toyota announced that it was backing away from the slow-selling electric RAV and no other joint projects were in the offing.

Instead Toyota said it would focus its efforts on fuel cell technology and would develop of its own fuel cell car—and it did. The Toyota Mirai, whose other-worldy styling matches its 21^st century technology (hydrogen fuel in, water vapor out) went in sale in Japan this week. It launches next year in Southern California with a sticker price of $57,500 or leases at $499 a month.

The Mirai can’t compare with Tesla’s Model S in speed or style. It takes a pokey nine seconds to accelerate to 60 miles per hour and lacks luxury features like the Tesla’s s 17-inch touch screen control pad. But Toyota claims a 300-mile range for the car, comparable to Tesla’s most expensive model, and its hydrogen fuel tanks can be replenished in as little as five minutes, compared with the hours usually needed to recharge a Tesla.

Characteristically, Toyota has revealed only modest sales targets for the Mirai. It plans to sell just 200 in the U.S. in 2015 and expects that number to climb to only 3,000 by the end of 2017. Like other alternative fuel cars, fuel cell vehicles lack an infrastructure to support them. As Mirai volume grows, Toyota plans to build out a network of hydrogen refueling stations in California and New England.

Other makers are climbing on the fuel cell bandwagon. BMW is collaborating with Toyota on powertrain development, and it will unveil its first-ever fuel cell drive system at the Detroit show. It is expected that the system will find its way into a new model for BMW’s i line of alternative fuel urban vehicles, joining the i3 and i8.

Audi will be showing its fuel-cell powered A7 Quattro, which goes a bit further than the Mirai on a tank (310 miles) and is a good bit faster, reaching 62 miles per hour in 7.9 seconds. Also on display at Detroit will be the Hyundai Tucson fuel cell crossover, which begins leasing ($499/mo.) in June and claims a 265-mile range.

Even Volkswagen is getting in the game. A little more than two years ago, VW CEO Martin Winterkorn famously panned the technology, saying “I do not see the infrastructure for fuel cell vehicles, and I do not see how hydrogen can be produced on large scale at reasonable cost.”

So what happened? A year later, Winterkorn had changed his tune, although he said a production fuel cell car is “still very far away.” And at the Los Angeles auto show in November ,Volkswagen presented the world premiere of the Golf SportWagen HyMotion—a research vehicle with a fuel cell powertrain.

Tesla CEO Musk calls them “fool cells” and says they are “mind-bogglingly stupid,” adding “hydrogen is suitable for the upper stage of rockets, but not for cars.” He may be right. Not for nothing have fuel cells been derided as “the technology of the future—and always will be.” We’ve seen fuel cell frenzy before. Those with long memories will recall General Motors pledge—taken before bankruptcy intervened—to develop a production-ready fuel-cell vehicle by 2010. Instead, we got the Volt.

But, as things stand now, neither Musk nor Tesla will be around the Detroit show to further their argument that batteries are superior.