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The first "automobile" or independent boat carrying its own battery was already demonstrated in 1838, and at the end of the 1870s one even made a trip across the English Channel. However, as with battery powered electrical boats and steam barges, the propeller created a wash and thus posed similar problems to the canal banks. They only saw limited use for unmanned mules, for instance in tunnels and in ports - an obvious advantage of most of these unmanned systems was that they kept the banks of the canal free. With the exception of funicular boats, all electrical systems were fed by a trolley line. Below is a picture of what seems to be the only propeller powered trolleyboat line that was ever operated in a commercial way. The boats were propelled by a moving cable on each bank, carried on supports provided with pulleys, and operated parallel to the canal. The line formed part of a 47 kilometre (29 miles) long trajectory served by electric mules (see further) and was only operated for a couple of years. One trolleyboat line is still in use. Also in this case, the trolley line was used to cross a subterranean tunnel, this one ("tunnel de Mauvages") being almost 5 kilometres (3.1 miles) long.

Your telephone only uses two wires (one pair), but dating back to the '60s it has been a widespread convention to wire homes for two separate telephone lines. This necessitated two wires for boats going in each direction. The nearly two dozen states that have restructured their local industry, forcing utilities to sell their generation assets to conglomerate holding companies, in order to "compete," must return responsibility and oversight for electric generation and disribution to the state utility commissions. The two electric motors (of 25 HP each) powered two screw propellers and received current from a pair of wires suspended over the canal through two ordinary underbearing trolley poles (picture on the right). The New York City blackout was the result not of a Summer heatwave, but of the decades of underinvestment in the infrastructure that distributes electric power from central feeder lines, through transformers, to the wires that deliver power to each home, school, factory, office building, small business, and hospital. FERC has been trying to force the TVA to join a Federally regulated Regional Transmission Organization, which would require it to cede control of its transmission grid, and force it to build new transmission capacity (for which its customers would have to pay), not to service its own ratepayers, but to allow "economy" wheeling over its wires.

As has often been noted, FERC has never met a utility merger it didn't like. In most countries, animal traction remained the only method in use on the canals, until it was superseded by diesel engines in the 1930s or later, or until the canals fell into disrepair altogether (like in the United Kingdom). The same method was once applied to boats, too. The propeller or paddlewheel would create the same wash as a steamboat, destroying the delicate canal banks. Manned electric mules - engine on the banks. Unmanned electric mules - engine on the banks or over the water. In those times, canals were simply a large ditch without reinforced banks. In the US in 1880, the total length of canals was around 7,200 kilometres (4,500 miles). This means that for every litre of fuel, a barge towed by a machine on the banks or via a chain on the bottom of the canal could carry a tonne of cargo for 500 kilometres (310 miles) - ten times more efficient than a truck or lorry. If all barges would be equipped with steam engines onboard, or towed by steam boats, then the wash of the screws (or paddlewheels) would have destroyed the banks of the canals in no time.

Funiculars - engine on the banks. Before diesel power took over, engineers developed several interesting methods powered by electricity: trolleyboats, floating funiculars and electric mules. In the US, electric mules were tested, what is electric cable but none of them were ever put in operation. Apart from some regional success stories, none of these technologies found widespread use, in spite of the many successful tests. A couple of years ago in Philadelphia, workers for PECO Energy found that some underground utility cable still in service dated to 1899. In July 1999, the failure of outdated cable was blamed for power outages in Manhattan affecting 200,000 people. And as seen in New York City this past July, breakdowns in 100-year-old underground local distribution systems are now leaving tens of thousands of people in the dark, and must be replaced. Some systems were afterwards converted to diesel engines. Most of these systems were initially powered by steam engines, and later adapted to electricity, which made them much more efficient and practical.