The 10-year-old Tate website, which receives over 18 million visitors a year, currently uses hand-coded HTML files. This will be replaced with a Drupal 7-based platform to move the site from a "brochure approach" to a social platform, encouraging debate and interaction about art as well as supporting user-generated content.
John Stack, head of Tate online, said the project to completely overhaul the site has already been two years in the making.
"Tate's website is 10 years' old and has never had a website re-design. We're in the process of overhauling, updating and re-designing every page and every system powering it," he said.
Stack said a lot of the website is based on hand-coded HTML files, meaning website updates are done manually, which is time-consuming and means only skilled personnel can make changes.
The organisation has also made changes to its hosting capabilities to cut costs.
"Previously, we would want to deploy pre-supplied software, such as e-learning and open source software, only to find that we needed specific versions of PHP or MySQL. As it wasn't in the package, we faced additional costs and had to go round the houses to find money. We had no time to wait around, working out what to do with hosting," said Stack.
Tate used "bits of cloud hosting" and decided to re-launch with a new hosting package from service provider NTT Europe called Compute Cloud.
Rob Gethen Smith, information systems director at Tate, said, "The decision to move into the cloud was sparked by plans to refresh the front-end of the main website and ambitious plans to increase online interactions and discussions about art. We wanted a solution that would support our growth and innovation."
Stack believes the changes to Drupal and cloud hosting will help the organisation provide a sustainable service for visitors, despite costing "quite a lot of money" in the face of budget cuts.
"The website gets bigger and yet we have less money after the [government's] Comprehensive Spending Review. With the ambition to do more and more, we need a more sustainable solution," he said.
"The choice of NTT and Drupal was all focused on making these things sustainable. The reason for that was Drupal is very mature and has a large community so it's easy to find people to work on the site. It also has a lot of community features for blogging, commenting and user profiles."
The move will also allow Tate to change the focus of its website.
"The site has acted as a brochure for marketing as well as the digitisation of 68,000 artworks in the Tate collection. It also provides learning resources and research materials, including audio visual and videos. That's been the focus for four years," said Stack.
He said the museum is now aiming to respond to rapid developments in mobile technology. Visitors will shortly be able to access the site when inside museums. The group hopes to launch a mobile version of its website after the main launch at the end of October, and to add to its portfolio of mobile apps for Apple's iPhone, including games and photos themed around particular exhibitions.
Stack said the organisation plans to produce apps for Google's Android operating system in the near future.
"At the moment we have to outsource because our web department specialises in web technologies. It's expensive because the skills are high in demand. But we'll think about bringing [mobile development] skills in-house in the future," he said.
The Tate has a web department of 12 people, six of whom are working on temporary contracts for the website re-launch.
Tate also announced a sponsorship partnership with Vodafone to support a new platform called Tate Debates - a weekly online discussion platform on Tate's blog.
Marc Sands, director of Tate Media, said, "Engaging with a global online audience, as well as our millions of gallery visitors, is an increasingly important part of what Tate does and I am sure our work with Vodafone will open up even more exciting and diverse ways to make this possible."
Twitter recently launched a new developer community site using Drupal, provided by Acquia.