Porsche said it would come out with electric sports cars in the future, but left the specifics to be revealed at a later date.

The company, in conjunction with Siemens and others, has shown off an all-electric Boxster at trade shows. We took this picture of one of the three all-electric Boxsters earlier this year at the World Future Energy Summit in Abu Dhabi. Now, Porsche says it has been testing the prototypes on the track and will come out with a car in the future.

"We will definitely be offering electric sports cars in the future," said Michael Macht, the President and CEO of Porsche AG in a prepared statement. "But such a concept only makes sense if it offers performance and a cruising range comparable to that of a sports car today."

Porsche last year got absorbed into the House of Volkswagen, which has been warming slightly to electrics and hybrids. Dr. Martin Winterkorn -- the CEO of the conglomerate that makes Volkswagens, Audis, Lamborghinis and Skodas, among other cars -- came to Palo Alto earlier this month and told many publications that Volkswagen will play a key role in electrified driving.

The conglomerate in 2009 also hired Tesla co-founder Martin Eberhard (reported here first).

But the group isn't going overboard. Last September at the Frankfurt Auto Show, the group showed off an all-electric Audi for 2012 and an all-electric Volkswagen, called the E-Up, for 2013. Volkswagen executives said that all-electrics might constitute 1.5 percent to 2 percent of its sales by 2020. A few months later, the company began to show off a Touareg hybrid for 2011. 

Winterkorn this week said that Volkswagen might also come out with an electric version of the Golf in 2013, thus adding another car to the lineup. He also added that hybrids and electrics might constitute three percent of sales by 2018. This could be a slight increase or decrease depending on how you count the hybrids. Either way, it puts Volkswagen on the low end of the market. Nissan-Renault has said ten percent of its cars will be all electric by 2020. Ford has said 25 percent of its cars will be hybrids, plug-in hybrids or all-electrics by 2020, with the vast majority of that total being hybrids.

In all likelihood, Volkswagen's heart will remain with diesel and clean diesel. Last year, the company sold out of diesel Audis and Volkswagens in the U.S. "We think that diesel could grow to around 15 percent of the [U.S.] market," Johan de Nysschen, president of Audi of America, told us in the fall of 2009. Actually, that will be true for most car companies. Ford, for instance, will likely sell a lot more EcoBoost engine cars, which get 10 percent to 15 percent better mileage than electric cars. But most car makers are a bit more gung-ho on electric.

Historical note: Dr. Ferdinand Porsche built the first hybrid in 1902.

Tags: all-electric cars, audi, diesel, electric sports cars, honda, nissan leaf, porsche, tesla motors, volkswagen