One of the most spacious, luxurious motorhomes at this month's RVX show was also created to be one of the most efficient Class As at camp. The one-off Thor Tuscany motorhome concept drops its diesel generator in favor of a massive lithium battery bank and solar panel array. It also includes a fully reworked, residential-style interior with two fireplaces, multiple power-retractable TVs, and handy innovations like a pop-out indoor/outdoor induction cooktop. This Tuscany isn't ready for market just yet, but it is a sign of things to come.

Stretching 45 feet (13.7-m) in length, the feature-packed Tuscany 45JA is Thor's flagship Class A motorhome, making an ambitious base vehicle for a lithium-powered concept. The fully expandable RV usually relies on a Cummins Onan 10-kW diesel generator, 300 watts of solar and six auxiliary house batteries to keep its power-hungry equipment running when not plugged into shore power. With the RVX concept, Thor leaves the slide-out Onan behind, enabling campers to cut the shore power cord without running a loud, emissions-spewing generator to keep electricity flowing.

Thor doesn't seem to have a proper name for its Tuscany concept, so we'll just call it the Tuscany Lithium, since the beefy lithium battery-based electrical system is the unequivocal highlight. To get more specific, Michigan's Volta Power Systems developed an electrical package with 36.4 kWh of automotive-grade lithium-ion battery storage concentrated into two large packs stored on a slide-out tray in the temperature controlled compartment up front. Volta and Thor are rather vague on details about what those batteries can power and for how long, but they do say they're powerful enough to operate all onboard electrical equipment and keep the air conditioner blowing for a comfortable midsummer night's sleep.

Running the power-hungry equipment of the spacious Tuscany will still deplete the batteries, and likely sooner rather than later, so Volta gives the system three charging solutions. Traditional shore-power charging relies on three pure-sine inverters for roughly 11,000 watts, while a 540-watt roof-mounted solar panel array provides an off-grid option. The third system should see a lot of use, especially during long tours with short overnight stops, running an 11-kW 58V alternator off the powerful diesel vehicle engine so that the batteries charge during driving. The charging systems can work independently or together, and an auto shutoff stops charging once the batteries are full.

Volta estimates the weight of the total system at 600 lb (272 kg), which is actually less than the 767-lb (348 kg) generator it replaces.

Volta's intention is to make lithium set-ups that last the lifetime of the vehicle, and it wires in a smart management system that cuts off battery power when the batteries drop to 10 percent, helping to ensure a longer lifespan. In the Thor video below, Volta cofounder and director of operations Jack Johnson says the Tuscany Lithium's batteries will retain 80 percent of their capacity after 10 years of use (2,000 cycles). He cites a general vehicle life expectancy of eight to 10 years, but mentions that in relation to cars, not motorhomes.

US Bureau of Transportation statistics show the average age of American automobiles increasing steadily over the last two decades, from 8.2 years in 1995 to 10.1 years in 2017. At the same time, America's RV and motorhomes were much older, rising on average from 13.2 years in 1995 to 15.8 years in 2017. The discrepancy seems intuitive enough – you drive your car every day, but you might only drive a motorhome a few times a year.

We suppose lower onboard electrical usage will follow less frequent RV usage, but the different ages and use cases of American cars and RVs does raise questions about how much life is enough for an expensive, custom-built RV lithium power system and whether auto industry-based lifecycle testing is applicable. It's not a big concern for a concept vehicle like the Tuscany Lithium, but it's something for consumers to keep in mind as production RVs make the switch from generators to lithium power.

The RVX show was all about previewing the future, and Thor didn't stop at the Volta electrical system, overhauling the Tuscany Lithium cabin with a more modern, residentially inspired design. We'd say they're quite successful in creating an updated look worthy of the huge living space, a nice improvement over the stuffier, over-glossed 2019 Tuscany interiors.

The range-topping Tuscany 45JA floor plan introduced last year already offers a very roomy, homey interior space thanks to the dual slide-outs on either side. Highlights include a rear master bedroom with walk-in closet, roomy dry bath layout with his/hers sinks, kitchen and bedroom fireplaces, and a 566-L residential French door refrigerator.

From there, Thor strips the cabin down from floor to ceiling and builds it back up with a rustic-contemporary look that's much less "RV" and more modern condo or apartment. The dark, flat-finish cabinets, moldings and frames are offset with light-beige, wood-look flooring, metal cabinet hardware and trim, off-white countertops, and multi-tone walls and accent walls.

The interior equipment package comes updated with the latest hardware and features, some of which will launch on the production 2020 Tuscany. One such feature headed for production is the full-length heated tile floor, which lets you walk barefoot in complete comfort, year-round. Another feature coming next model year, the large, unbroken countertop is pieced together with counter-matched covers for both the set-in induction cooktop and stainless steel apron sink. Interestingly, the cooktop quickly pops out of the countertop for outdoor use, a nice bonus for tailgaters and others who enjoy cooking outside.

The Tuscany concept rides on a 2020 Freightliner diesel RV chassis, complete with the new OptiView all-digital instrument panel. As a Daimler brand, Freightliner taps into the in-vehicle tech expertise of Mercedes-Benz, modeling the OptiView after the dashboard of the Mercedes S-Class. The new system combines traditional gauge data with multimedia information, full 360-degree camera integration, Bluetooth connectivity, and touchscreen and physical steering wheel controls.

Thor complements the OptiView with an all-new 15-in Garmin touchscreen infotainment system that merges together RV-specific navigation with multi-zone Fusion audio and infotainment features. The tablet-style touchscreen can be split into sub-screens for optimized viewing of mapping, audio, onboard systems data and camera feeds. Both the OptiView and 15-in Garmin system will be packaged into the 2020 Tuscany.

To finish it all off with a proverbial bow, Thor splashes on a vibrant custom paint job with fades, shadows, visual texturing and mirror-polish finish.

Unlike some of the other luxurious Class As we toured at RVX, the Tuscany Lithium didn't have a pricing sheet inside because it's a one-off concept with a number of features that may or may not ever see production. That said, Thor mentions more than once that certain features are what you'd expect from a seven-figure motorhome. The base 2019 Tuscany 45JA starts at US$479,850, without the Volta power system, conceptual interior or MY2020 features.

Thor put the Tuscany concept out there at RVX for people to have a look and offer feedback. The company intends to consider that feedback when moving forward with future product planning. We certainly hope to see Thor, and the RV industry at large, follow the auto industry in moving slowly but steadily toward electric power, and we look forward to camping next to more RVs running silent lithium in place of rumbling generators.

As it did with the Sequence concept camper van, Thor really dove into the details in its Tuscany Lithium videos. The first 18-minute video below walks through the electrical layout with Volta's Jack Johnson, while the 22-minute video that follows it looks more closely at the interior features and aesthetic details. If you don't have that kind of time to dedicate, you can walk through the interior more quickly in our photo gallery and compare the concept styling with a few interior photos of the 2019 Tuscany 45JA.

View gallery - 19 images