Unplugged: Making an electric car is hard, making one commercially viable is even harder. Just ask Sir James Dyson, Britain's richest entrepreneur, who spent £500 million ($605 million) of his own money on developing a Tesla rival, an ambitious project that turned out to be a rather short-lived dream defeated by cold-blooded economics and harsh realities of the electric car business. In a recent interview with the Sunday Times, the famed inventor stood by the Dyson electric 7-seater SUV and gave an insight into why the prototype was unable to make it to public roads.

A lot of vacuum cleaner-related jokes ensued when Dyson announced its plans of entering the electric car business back in 2017. The situation, however, became rather grim in October last year, when the company abandoned its electric car program over lack of commercial feasibility.

Outside of legacy carmakers, who've recently begun proliferating their electric offerings and investments in the technology, new entrants don't have the luxury of chewing through vast sums of capital for R&D, the required infrastructure for mass production, nor the brand cachet to drive initial consumer interest.

Even Tesla, which is arguably spearheading this industry, is not devoid of financial problems, among others, as is often reflected in the company's quarterly earnings or in the eccentricity of some of Elon Musk's tweets that often do more harm than good.

With that said, Dyson's multi-year effort with electric cars saw it making noticeable progress on numerous fronts such as solid-state batteries, machine learning and AI technologies. It even had a driveable 7-seater SUV prototype, propelled by two 200kW electric motors, taking the 2.6-ton vehicle from 0-60 mph in 4.8 seconds and on to a top speed of 125 mph.

Although no specifics were given regarding the battery capacity or layout, the lithium-ion pack was rated for an impressive 600 miles of range helped by the rather large but low rolling resistance tires and a windscreen that's more steeply raked than that on a Ferrari.

While the aerodynamic car would have cut smoothly through the air, what ultimately blocked its path were the higher costs associated with manufacturing batteries, electronics, and cooling technology. Consequently, the Dyson SUV would have ended up costing a hefty £150,000 just to break it even.

Legacy automakers like Audi, BMW, Jaguar Land Rover and Mercedes "are making huge losses on every electric car they sell," says Dyson, noting that these car makers can subsidize costs of their electric cars with sales of traditional petrol and diesel models and are incurring these losses "because it lowers their average CO2 and NO2 emissions overall, helping them to comply with EU legislation."

He also rubbished the notion of Dyson's electric SUV being a "vanity project," stating that the company had a viable tech platform and an efficient long-range car as far back as in 2014, but the venture became too risky when other companies started producing electric cars at a loss.

The company, however, is still looking to maintain its presence in the electric car market by developing solid-state batteries, the alternative to existing liquid-based Li-ion battery packs, deemed to be much smaller, lighter, easier to cool and recycle.

"Other people are developing solid-state batteries. We may be the first. If what we’re doing turns out to be suitable for other people, then that’s an option," notes Dyson, adding that he might have another go at electric cars, provided that commercial circumstances are suitable.