* Britain, trailblazer in online grocery, seen at 13.7 bln euros
* Grocery e-commerce also set to take off in Germany, Netherlands
* Supermarkets embrace "click and collect" to boost online
BERLIN, Oct 24 (Reuters) - Online grocery sales will roughly double on average by 2016 in five key northern European markets - Britain, France, Germany, Switzerland and the Netherlands - the food and consumer goods research group IGD said on Thursday.
IGD predicted that online grocery shopping in Britain would be worth 13.7 billion euros ($18.9 billion) by 2016, up from 7.1 billion in 2012, while the French market should grow to 10.6 billion euros from 5 billion last year.
"Online retailing in food and consumer goods is growing at a phenomenal rate across Europe. Technology is empowering people, fundamentally changing the way they buy groceries," IGD chief executive Joanne Denney-Finch said in a statement.
British retailers have been trailblazers in moving to sell food online, with the business growing 16 percent a year, although the delivery logistics for chilled products are much more complex and expensive than for non-perishables.
Even Amazon has made only tentative steps into grocery, but it is now preparing to expand its "Fresh" business to 20 urban areas in 2014. It says that it may expand outside the United States, but has not specified where.
The British online grocer Ocado said this month it expects to agree more and more joint ventures with retailers outside its home market, mirroring its deal with the British supermarket chain Wm Morrison.
IGD said even Germany, where dominant discounters Lidl and Aldi have not embraced online grocery selling, would see sales grow to 2.5 billion euros by 2016 from 1.1 billion in 2012.
It said the Dutch market would leap to 1.6 billion euros from 0.6 billion, and Swiss online grocery sales would rise to 1.1 billion euros from 0.7 billion.
Some European retailers such as Tesco, Wal-Mart's Asda, Carrefour and Ahold are building hundreds of collection points to give shoppers more flexibility in how they receive their online orders.