Outdoors

All-electric off-grid glamping trailer ditches gas for solar power

All-electric off-grid glamping...
The ERV will be offered on both a single- and dual-axle platforms
The ERV will be offered on both a single- and dual-axle platforms
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This prototype traveled 12,400 miles around Australia to test out the CEMS electrical system
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This prototype traveled 12,400 miles around Australia to test out the CEMS electrical system
The kitchen includes a sink, induction cooktop, fridge and oven/grill and can support plenty of accessories
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The kitchen includes a sink, induction cooktop, fridge and oven/grill and can support plenty of accessories
Tile backsplash behind the two-burner cooktop
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Tile backsplash behind the two-burner cooktop
Retreat debuted the polished ERV at the Melbourne Leisurefest in October
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Retreat debuted the polished ERV at the Melbourne Leisurefest in October
The ERV will have several floor plans; this one includes an open bedroom area and central dinette and kitchen
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The ERV will have several floor plans; this one includes an open bedroom area and central dinette and kitchen
The ERV will be offered on both a single- and dual-axle platforms
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The ERV will be offered on both a single- and dual-axle platforms
The OzXcorp CEMS mounts the 14.3-kWh lithium battery neatly in the end of the chassis
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The OzXcorp CEMS mounts the 14.3-kWh lithium battery neatly in the end of the chassis
Retreat ERV interior
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Retreat ERV interior
Map of the 12,400-mile journey during which OzXcorp/Retreat tested the electrical system over the course of six months
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Map of the 12,400-mile journey during which OzXcorp/Retreat tested the electrical system over the course of six months
The ERV feels like home with its basin sink and marble-style counters
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The ERV feels like home with its basin sink and marble-style counters
Inside the Retreat ERV
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Inside the ERV
Retreat Caravans ERV
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Retreat Caravans ERV
The ERV will start at $109,900 in Australia
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The ERV will start at $109,900 in Australia
Retreat Caravans ERV
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Retreat Caravans ERV
Up to 2,033 watts of solar panels find home on the roof
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Up to 2,033 watts of solar panels find home on the roof
View gallery - 15 images

The new ERV from Retreat Caravans travels to the most distant corners of Australia and beyond, using only electric power to keep equipment running. That would be a nice feat for an RV as simple as a tiny teardrop trailer, but the ERV is more a dual-axle luxury condo. Its lithium battery and solar roof power the all-season climate control, indoor/outdoor entertainment system, electrified kitchen and even washing machine. Leave the LPG tanks and electrical grid behind, explore Outback-style remoteness and live like a kingly nomad in a high-tech hideaway.

Electric motorhomes and pickup campers have stolen the spotlight throughout 2019, but all-electric caravans have been quietly creeping forward in the backdrop. In the US, Thor Industries, the world's largest RV manufacturer, worked up a more rigid definition of "off grid" with the Sonic X caravan concept back in March. Later in the year, another brand under the Thor umbrella, Germany's LMC, followed suit with its own electrified trailer at the Düsseldorf Caravan Salon. The two models were quite distinct, but both shared the same goal: leaving behind every last trace of liquified petroleum gas (LPG) and tying together all onboard equipment with a single electrical architecture.

Australia's Retreat Caravans goes beyond concepts, breaking free from LPG with what it calls the world's first fully electric caravan, the ERV. It relies on a Centralized Energy Management System (CEMS) supplied by Australian caravan tech startup OzXcorp. Co-founded by Andrew Huett, a businessman who spent nearly two decades living completely off the grid and has racked up some 43,000 miles (70,000 km) traveling around Australia, OzXcorp was formed to bring caravan tech and design into the smart age. With the CEMS, OzXcorp hangs an automotive-grade 14.3-kWh lithium battery pack inside a galvanized steel chassis and distributes power through a 48-volt electrical architecture.

The OzXcorp CEMS mounts the 14.3-kWh lithium battery neatly in the end of the chassis
The OzXcorp CEMS mounts the 14.3-kWh lithium battery neatly in the end of the chassis

The CEMS battery has roughly 12 times the kilowatt-hour capacity of the 100-Ah batteries common in RV construction, and Retreat needs every last watt-hour. Resisting any temptation to pare down features to conserve energy, Retreat loads the ERV with a lengthy equipment list that pushes well into glamping territory. That list includes both heating and A/C; a water heater; a washing machine; a comprehensive entertainment system with 24-in smart TV, indoor/outdoor stereo speakers and available outdoor TV; LED lighting; and the aforementioned kitchen with dual-burner induction cooktop, convection oven/grill and 274L standing-height fridge/freezer. For its show trailer, Retreat even accessorizes the kitchen with an electric coffeemaker, kettle and toaster. Outside, there's a slide-out Weber electric grill and separate 36L fridge freezer. All equipment is powered off the battery, and a CZone smart command center offers full digitized monitoring, control and problem diagnosis.

Retreat ERV interior
Retreat ERV interior

To shore up efficient energy usage, Retreat relies on a new composite construction with optimized thermal insulation, helping the cabin retain heat in colder weather and cool air in warmer temperatures. The all-electric design in turn streamlines construction, eliminating the need for the exterior venting needed for gas appliances, thereby making it simpler to seal and dust-proof the shell. Eliminating vents that interior air could escape through also improves thermal efficiency.

The ERV's 5,000-watt inverter can keep multiple appliances and components humming all at once. At shows and events, Retreat demonstrates this capability by dropping bread slices into the toaster, switching the kettle on, firing up the cooktop and blowing the hairdryer, all with the air conditioning running in the background. That sounds more like a weekday work morning than a camp morning, so the ERV shouldn't have trouble keeping up with a more leisurely holiday routine.

Up to 2,033 watts of solar panels find home on the roof
Up to 2,033 watts of solar panels find home on the roof

The ERV does of course include a shore power hook-up for times it's parked in a fully equipped campground, but it's really built with off-grid travel and living in mind. It pulls charge from the tow vehicle while driving and includes a robust roof-mounted solar array that packs up to 2,033 watts, depending upon floor plan and overall roof length.

During the prototype phase, Retreat and OzXcorp put the ERV through grueling real-world testing, traveling more than 12,400 miles (20,000 km) through the heart of Australia over six months. The goal was to make the trip relying solely on solar power, keeping the trailer unplugged from both the tow vehicle and all shore power hook-ups. The travelers did have to connect a back-up generator when the battery dropped particularly low during shady conditions, but beyond that, they remained true to the goal of relying on solar power. At one point during the journey, the ERV was even powering its own equipment and two additional caravans.

This prototype traveled 12,400 miles around Australia to test out the CEMS electrical system
This prototype traveled 12,400 miles around Australia to test out the CEMS electrical system

The ability of ERV buyers to have the same kind of fully unplugged trips will depend upon their power usage and available sun. Even knowing a little about how luxury-laden Australian caravans are, we're surprised with just how much battery-sapping equipment Retreat has loaded into this one, since it could have easily left off or sized down a few of those components. But we guess the point was to make a strong statement about how campers don't have to skimp to go electric.

The ERV carries water in an isolated 65L drinking water tank and two additional 110L tanks. The large interior fridge and outdoor auxiliary fridge help ensure travelers have plenty of fresh food on hand when traveling to remote locations.

Retreat debuted a more refined, production-ready ERV at the Melbourne Leisurefest in October and is completing work on the first ERV-1 Off-Road, an 18.6-foot (5.7-m) model. From there, it intends to offer several different floor plans on various length single- and dual-axle trailers. A Cruisemaster TS off-road suspension and Mickey Thompson all-terrain tires will eat up the type of off-grid ground for which the ERV's impressive electrical underpinnings are engineered.

The ERV will start at $109,900 in Australia
The ERV will start at $109,900 in Australia

Retreat tells us the ERV will start at AU$109,900 (approx. US$75,625), and we'll look to publish a more complete breakdown of layouts, standard features, options and prices after the first models push their way out of the production facility. For those interested in doing some power math, Retreat has wattage figures for the various electrical components and accessories listed on the ERV homepage linked below.

The video below dives into the ERV experience with John and Fran Huett, the couple who made the cross-country prototype trip.

2019 ERV - 17,000km in a Fully Electric Caravan | Truly Off-Grid Experience

Source: Retreat Caravans

View gallery - 15 images
9 comments
guzmanchinky
For me the best part of this would be running an A/C at night without having to run a noisy generator. LP still has massively more power per weight, and it's great for heating and cooking and even the refrigerator is silent, but not the generator which is needed to run the A/C...
VincentWolf
Full 40 foot BEV powered RVs wont be far behind that leave behind the diesel motor for morion, the LPG for stoves, the gas generator for night time power, etc and the entire industry is going to change to full battery and solar power within 10 years and those with the old diesels will be stuck with stranded assets.
f8lee
Okay, now I'll wait for Tesla's pickup truck to become available and I will have a completely off the grid kit!

Hmmm...if the trailer's solar panels could keep the Tesla charged, range would be limitless!
Bruce Warren
So, "the battery dropped particularly low during shady conditions". Yup, the battery will be low most all the time if you use the appliances listed in the article. Electric water heater... are they nuts? Propane is cheap and a perfect solution for providing hot water or hot air or baking a pie. For 3 years I have been experimenting with a parked motorhome with a 5kw inverter, 1200 watts of 24volt solar panels and two banks of 6volt golf cart batteries that are 200 amp hour rated, which makes 400 amp hours of 24 volt battery power. On the Texas coast with the panels pointing due south at a 30 degree angle, the panels put out a maximum of about 30 amps at high noon with a clear sky in July. That is 750 watts, less than 2/3 of the stated rating. I guess you have to be on the equator at noon to get the nameplate output from a solar panel. A sunny day near Houston will deliver that 30 amps for about 6-7 hours. Then you get shadows from distant trees and almost always some clouds. Any shadow at all knocks the output down to just 3-4 amps. The Retreat ERV has 1400 amp-hours of battery storage... that is really nice, about 4 times my golf cart batteries. But the big problem is the sky in the US is sunny about 200 days a year. It is very likely you will take your vacation during a week with very little output from the solar panels. You must find an RV park to plugin each night.
BlueOak
Cool stuff. If you live in a weather-free, tree-free, cooling-climate location. Otherwise, having propane for heating and at least a modest sized backup genset would be required.
Richard
We’ve had an off grid home for 12 years! Refrigeration, Hot Water and AC require the most energy. The new D.C. refrigerators and freezers are very efficient however. 14KW of batteries require at minimum 4KW of panels or a backup propane D.C. plant both are best. We cook, heat and make hot water with propane. In hot climates you need A.C. 24/7! You need enough power to run A.C and charge together. Panels laid flat generate about 70% of rating at noon at 30 degrees latitude with additional derating for high temperatures. 2KW isn’t enough solar for winter or high summer clouds (up to 60% reduction)! A plant for peak loads and batteries for overnight as well as sunny days is the best mix. Using a small instant hot water heater solves that problem if you have propane anyway.
Ponobill
I've updated a 1978 GMC motor home with 1860watts of PV, 10KWh of Tesla modules and a 6KW inverter as well as radically changing the interior and building a power management system. No propane, no adsorption-based refrigerator. Using MPPT controllers and 310-watt panels I actually get more than the rated 1860 watts with the panels flat and Oregon summer sun angle. Equating golf cart batteries to Lithium is tricky--if you want your lead-acid batteries to last you don't discharge beyond 50%, so 1600AH lithium is more like six times a 400AH LA battery. The LI pack can be discharged much lower and while it will last decades if it's charged to 85% and discharged to 15%, true capacity is actually close to 100 percent. Part of the solution to ditching propane is choosing the right components, part of it is managing energy use. I made an energy management system that prioritizes energy use based on available power. The bedroom AC is a mini-split I modified to run on 24VDC which uses 900 watts to deliver 12K BTU. The central AC using a conventional RV AC is a huge starting load and sucks 1840 watts, almost 80 amps to the inverter. Conventional RV's use fairly wasteful appliances because they are designed to be connected to shore power and to use Propane for a lot of stuff. Ditching propane takes more than just adding electric appliances, but it's feasible, even without the resources of a manufacturer. I wrote about some of this stuff on a blog that I sometimes update. The entries on Fritz, my GMC moho are out of date, but have some useful information: www.ponostyle.com
vince
The day of the diesel RV are soon past. In about 5 years, certainly no more than 10, you won't be able to buy a diesel RV except used. And they will cost pennies on the dollar and so depreciation for the owners is going to be intolerable leading some into bankruptcy.
John Anderson
All very well for you Oz neighbourhood but us Kiwis who do experience a lot of cloudy rainy days, we might be more than happy to have a bottle of LPG hidden away in our.....diesel hybrid....buggies... Easy to be Green under the sun ☀️ if it shines each day, but tell an Eskimo he can’t burn blubber to keep warm!