Recently, I purchased an electric bike (ebike) for use around the homestead, and for physical training purposes. This is actually the third ebike that I've used over the past two decades, and there has been some remarkable improvements in their performance.
The first ebike I ever used was a 12 volt DC folding bicycle that had a metal roller which pressed against the front 20" wheel to drive the bike forward. Needless to say, that design was not efficient, as there was significant wear on the tread of the front tire. Also in wet conditions there was significant slippage and I had to pay strict attention to ensure the tire was kept properly inflated. The range was very limited, perhaps a distance of 4-5 miles. This particular ebike wasn't really capable of climbing hills, so the ebike utility was extremely limited. It used a 12 volt sealed lead acid battery, which was very heavy.
I next experimented with a home built trike, using a hub motor on the front wheel. The trike is low slung, so it is stable. The trike uses a three speed rear hub, when pedaling, so it can climb modest hills. The motor is 24 volts, and it uses conventional sealed lead acid batteries. Due to its construction, the trike is capable of carrying a large amount of weight, easily up to 300+ pounds, and there's a platform where cargo can be placed. The braking system is somewhat unconventional, as the front brake uses a typical v type clamps, while in the rear is a disc brake. The wheels are 20". The range with the current batteries is less than 10 miles, but it is capable of climbing hills. The plan is to eventually upgrade the batteries to lithium iron phosphate, which should improve the range and the performance of the trike, making it more useful around the homestead.
The latest ebike I purchased last year, and it already has over 300 miles on the odometer. It is a Rattan LF-750 step through design that also folds. Rattan has what they call IPAS (Intelligent Pedal Assist System) which increases the range of the ebike using regenerative charging. With a 13Ah, 48 volt DC battery, they claim a 60-80 mile range, and users on-line confirm they've gotten 70+ miles range from their ebikes, while using the pedal assist feature. This particular model has exceptional performance, easily mounting steep hills with its 750 watt motor. It's considered a Class 3 ebike with a maximum speed of 35 mph. I've had mine up to 49 mph. It has fat tires (4x20") so it works acceptably in grass, mud and snow. I haven't tested it in snow, but it works great on our homestead terrain. It has a 7 speed derailleur system, which is used in conjunction with the pedal assist system. The rear hub motor can be activated with a twist grip throttle or with the pedal assist system. With the pedal assist system it augments the users pedaling with 5 different settings, adding 10%-100% more power.
Because it can be folded, this particular model will easily fit into a car trunk or other compact spaces, like the back seat of an aircraft. The Rattan LF-750 can also carry a payload of 300+ pounds. It does have a luggage rack located behind seat over the rear wheel. In its original configuration, there was a padded seat for a child with a weight limitation of 25 kg. I removed the seat and installed a milk crate which will improve the utility of the bike. The overall performance of this model is impressive, and it seems to be well built, hopefully it'll last many years. Riding an ebike does provide a reasonable amount of exercise, depending upon how the operator uses the bike. I've found that in general, the pedal assist is used primarily when ascending hills, or when I need a boost of speed when evading aggressive dogs.
One of my neighbors recently purchased a Rad Power Bikes Radrunner. The Radrunner has similar performance to the Rattan ebike, but it is a Class 2 ebike, and the bike only has a single speed, no derailleur, so the maximum speed is 20 mph. So it is a bit slower, but it is just as stable, with wide, fat tires (3.3x20"). The Radrunner is capable of carrying 300 pounds, and has a reported range of 45 miles. The Radrunner does not fold, but it has an extremely sturdy aluminum alloy frame. Unlike the Rattan, the Radrunner does not have any integrated suspension, except for the fat tires. Overall, the Radrunner is a very well constructed ebike, built for rugged use.
I see modern ebikes as a supplemental mode of transportation. Most modern ebikes use some type of lithium battery as the power source. Lithium batteries, due to their design, have long life times, and remarkable performance characteristics. In most cases, lithium batteries can be discharged down to 10% without damage to the battery. Lithium batteries are also one of the lightest power options available. In a SHTF situation, an ebike battery can be recharged with solar power. So, a traveler could potentially travel in darkness 60-80 miles and then bed down for the day while the batteries are recharged, and the traveler could continue this process until he or she reaches their destination. The rider would need a minimum of a 100 watt panel to maintain a charge, and a foldable or flexible panel would be best. If the batteries become totally depleted, it's still possible to pedal the ebike to continue onward, unlike a gas powered motorcycle or ATV. Without the ebike motor, pedaling the bike is tedious, as a typical ebike is in the 60-80 pound range, but it can be done.
Like everything there are downsides to using an ebike for transportation. Cost is a big factor, as ebikes start around $1000, and the sky is the limit for maximum pricing. The Rattan LF-750 and the Radrunner are priced around $1500. Accessories are expensive too, as the Radrunner doesn't come with fenders or any suspension.
Ebikes are not totally silent, their motors do make a humming noise. Ebikes are much quieter than combustion motor vehicles, but the ebike motor noise is still audible, even when coasting.
You have no physical protection while riding an ebike, so the operator needs to be tactically aware. Some ebikes, like the Rattan LF-750, are susceptible to damage from water; so no riding through streams nor riding during heavy downpours.
An ebike has proven useful around our little homestead, especially as we've gotten older. It's a relatively quiet mode of renewable transportation. In a SHTF situation, an ebike could be used by roving patrols. An ebike could also be used for courier service too. It could be a last ditch mode of wheeled transportation before resorting to hiking. An ebike would be an excellent alternative method of transportation, if petroleum becomes scarce. We're happy we've added some to our mix of vehicles.