Thomas Thurner

Semantic Web driven tagging tool makes clean energy content searchable and findable!

New reegle API will tag online resources automatically – and suggest related content.

A new cost-free tagging tool is now available to anyone who provides online resources in the clean energy field. This API (application programming interface), developed by the Semantic Web Company, will automatically tag documents and web content that cover renewable energy, energy efficiency and climate-relevant topics according to the well maintained Reegle’s Clean Energy and Climate Change Thesaurus. It can also suggest related documents from the growing pool of content that has already been indexed using the tool.

Tagging” means that when integrated into a website, this API will automatically scan the site’s content and identify specific terms, concepts and geographic mentions and then apply tags to each so all resources connected with the site are searchable online.

By automating the tagging process, we can help ensure that content is classified in a consistent way across the entire sector, based on our Clean Energy Thesaurus” notes Florian Bauer, Operations & IT Director of REEEP. “This will help make major depositories of existing information open and accessible, and help promote clean, low-carbon development in the process.”

In addition to tagging, the API can also make suggestions for related reading from the web resources already indexed, thus enriching the content of any website. “Sharing your own indexed resources with the API content pool can increase the outreach of your documents hugely,” recommends Denise Recheis, expert in knowledge management at reegle.

Try out service

The tool is available at, where you can try out the API on the spot. Simply cut and paste a block of text, and a demonstration will show all of the concepts, terms and categories that the tool automatically generates.

Free API key

On this site, web developers can register to get a free API key for each project, with no limit on the number of keys. When logged in, the dashboard includes a request builder to help developers to build the necessary code. The service is available in five different languages: English, French, Spanish, Portuguese and German. The API returns the formats RDF/XML and JSON.


The reegle tagging API project is a collaborative effort with NREL (OpenEI), weADAPT and IDS (eldis), and was made possible by support from the CDKN Innovation Fund. For further information about the reegle tagging API Reeep’s Thesaurus and Knowledge Manager Denise Recheis is available.

Andreas Blumauer

Linked Open Data: The Essentials – A quick start guide for decision makers

Together with REEEP (Renewable Energy and Energy Efficiency Partnership) the Semantic Web Company (SWC) has composed a fundamental publication on the topic of Linked Open Data.

Linked Open Data: The Essentials provides answers to the following key questions:

  • What do the terms Open Data, Open Government Data and Linked Open Data actually mean, and what are the differences between them?
  • What do I need to take into account in developing a LOD strategy?
  • What does my organisation need to do technically in order to open up and publish its datasets?
  • How can I make sure the data is accessible and digestible for others?
  • How can I add value to my own data sets by consuming LOD from others?
  • What can be learned existing best practices?
  • What are the key potentials of sharing and consuming open datasets?

Read more about this publication and find out how to obtain a copy.

Andreas Blumauer

Florian Bauer: I like to view “linked data” as a “single worldwide API”

Florian BauerFlorian Bauer is REEEP’s Operations and IT Director, responsible for the overall operational management of the organisation, the product management of reegle (the search engine for renewable energy and energy efficiency) and the management of the IT landscape of REEEP.

PoolParty Team had the chance to talk with Florian about reegle – information gateway on clean energy.

Could you please give us a brief overview over reegle – what are the targets you are pursuing with this platform?

The main aim of the reegle information gateway ( is to provide a one-stop gateway to comprehensive, high-quality and up-to-date information on clean energy. By making this information accessible to stakeholders in the field around the world, and by presenting it in a user-friendly and intuitive format, reegle directly helps to facilitate the transition to low-carbon energy.

The website provides information on renewable energy, energy efficiency and climate change and their various sub-sectors at a global level, and some reegle services actually combine raw data sets from several different sources, put these datasets into context and thus provide enriched information.

reegle is an offshoot of the Renewable Energy & Energy Efficiency Partnership (REEEP), a non-profit, specialist change agent aiming to catalyze the market for renewable energy and energy efficiency, with a primary focus on emerging markets and developing countries.

The new reegle data portal (, launched in 2011, has established reegle as a publisher and consumer of Linked Open Data in the energy sector. It provides key clean energy datasets free for re-use using Linked Open Data W3C standards.

reegle consists of two components: one is the semantic search engine (, the other is the linked data portal ( – What are your target groups, and which typical problems of the clean energy domain can you solve with these services?

For, our target groups are primarily project developers, financiers and government policy-makers. These users can access high-quality information on clean energy-related issues with the set of tools we provide: a special web search, a catalogue of more than 1700 key stakeholders, a map view for geographical browsing, a clean energy glossary, and an energy country profiles function.

The energy country profiles are typical of what we’re trying to achieve. Here, we take information from many different providers and combine it all to present one comprehensive information dossier on renewable energy and energy efficiency in that particular country. This means that in one location you have the country’s most important energy-related information ranging from key statistics, and current regulations to key players in the energy field in both public and private sectors.

For our data portal, the target group is a more technical one: primarily IT developers and open data specialists who want to create new mash-ups and integrate data from reegle into other websites. One of the first using these reegle data sets is the website, another key portal in the energy field.

Open data is not the same as linked open data. Why did you choose to build your services around W3C´s linked data paradigm and/or standards like RDF?

Tim Berners-Lee once mentioned that he likes to compare the progressive ways of offering data with the “stars system” used to rate hotels. You get:

* for making data public (in any format)
** for machine-readable formats (structured data)
*** if the data is offered in a non-proprietary format
**** if you use URIs to identify things, so people can point to your datasets
***** for linking to other people’s data to provide context

So, as you can imagine, our goal is for reegle to be firmly in the 5-star category, and to establish reegle as an avant-garde tool in energy data.
I also like to view “linked data” as a “single worldwide API”. If the old web was like a huge book, the new semantic web is like a huge database, and SPARQL is the way to ask for information – by sending a query through the SPARQL Endpoint. RDF is the language that offers all possibilities to describe a given dataset with all of the necessary information, including any links to other datasets. Therefore RDF data and SPARQL endpoints provide a powerful tool to find and filter datasets and are crucial, base parts of the semantic web’s architectural layers. On reegle the SPARQL endpoint and the description of the structure of our RDF files is online on our clean energy open data portal.

You also decided to build a SKOS based domain thesaurus for clean energy which now plays an important role to improve the search experience at reegle.
Which experiences have you gained so far from this effort? Which obstacles did you have to overcome?

The SKOS-based renewable energy thesaurus can be seen as the “heart” of reegle as it provides the basis for a lot of related services in reegle, including the refinement suggestions for search results, the auto-completion options and the glossary links between defined terms and their synonyms and related terms.

We decided to use SKOS because we think it is the best language for building a formal and controlled vocabulary for thesauri in a semantic web context, without adding too much complexity. Although it is a simple language, you really still need IT experts to use it to build a thesaurus – domain experts with additional IT skills (hard to find!).

So in our case, we decided to use a scalable and easy-to-use thesaurus server called “PoolParty”. Using this system drastically reduced the complexity, and allowed us to concentrate on the actual building of the thesaurus with our domain experts, and to spend less time on transferring the knowledge into data sets.

What are your future plans with reegle?

Currently we’re working on restructuring the site to better highlight our new added-value services such as the clean energy country profiles. We are also planning to further develop our thesaurus to include climate-compatible development terms and we’ll soon release a wordpress plug-in to insert this thesaurus into clean energy blogs. One of the most exciting projects we are actually working on is the development of “dossier pages”, where we will provide relevant information to several topics mashed up on one page using semantic web technologies. This is part of the EU funded SCMS (“semantic content management system”) project.