Two million books will be available in an online digital library to rival Google's collection, according to Professor Robert Darnton, who promised the new database would overcome copyright hurdles by next year

An American digital public library of over two million books will be in place by next April, according to scholar, author and Harvard University librarian Robert Darnton.

Professor Darnton, speaking at Columbia Law School earlier this week, made the public promise that the Digital Public Library of America, a non-profit initiative first dreamed up in October 2010, "will be up and running by April 2013, and its initial holdings will include at least two million books in the public domain accompanied by a dazzling array of special collections far richer than anything available through Google".

With funding from the Sloan Foundation and Arcadia Fund , the Digital Public Library of America counts on its steering committee, a mix of non-profit and foundation leaders, government officials and academic and public library directors.

Darnton, who represents Harvard, said that the idea behind the library is to make America's "cultural heritage accessible, free of charge, to all of our countrymen and women, in fact to everyone in the world".

Although these plans have a "utopian ring" to them, Darnton confessed to "some sympathy" with utopianism when speaking at Columbia. "It challenges the assumption that the way things are is the way they have to be and that the everyday, workaday world is firmly fixed in what we take to be reality. History shows that things can fall apart, sometimes in a way that releases utopian energy."

The DPLA steering committee is currently wrestling with the issue of copyright – the same problem which Google ran into over its controversial plans to digitise millions of books for Google Book Search, eventually getting sued by authors and publishers for infringement.

Google Book Search was "originally … a great idea", said Darnton. "Thanks to its technological wizardry, its energy, its wealth, and its sheer chutzpah, Google set out to digitise all the books in the world's greatest research libraries." But then the search engine "stepped over the line that divided books in the public domain from copyrighted books".

The lessons to be learned from Google's "failed … attempt" are that it is possible to build a huge digital library, but that "such a library should be designed and run for the public good", said Darnton.

The DPLA, a non-profit organisation "devoted to the public good", must accommodate "the legitimate interests of the book industry" as it seeks to include books covered by copyright in its collection while avoiding "ruinous litigation". His own suggestion was to steer clear of books which have just been published, instead creating "a moving wall" of five or 10 years between the library's collection and books which are in print, which would advance a year at a time. "Most books cease to sell after a few weeks, and their potential to produce revenue dries up completely within a few years," he said. "The rare book that maintains its commercial value over a long time could be excluded from the DPLA by an opt-out arrangement with the publisher and author. Far from threatening the economic interests of rights holders, the DPLA might in this way win their cooperation."

Darnton finished by calling on his listeners not to let "concern with legal entanglements … blind us to the utopian energy that has driven democratisation from the time of the Founding Fathers".

"Given the opportunity, authors and publishers and readers of all kinds will rally to the cause," he said. "Their commitment can fuel the other force that shaped the Republic from its beginning. I mean the pragmatic, can-do spirit that actually gets things done. Therefore, I would like to conclude with a promise. We will raise the funds; we will design the technology; we will organise the administration; we will even … work through the legal problems; and we will get the DPLA up and running by April 2013."