About this building
Tate Modern is the home of Tate's collection of international modern and contemporary art. Formerly Bankside Power Station, designed by Sir Giles Gilbert Scott and built in two phases between 1947 and 1963, Tate's transformation of the Power Station began in 1995. A steel framework was built within the existing walls of the Power Station to create the seven gallery floors. This framework also supports the existing brick façade of the building. The architects were Herzog & De Meuron. Since it opened in May 2000, more than 40 million people have visited Tate Modern.
Our energy use
This graph allows everyone to access a range of data from Tate Modern. It's updated frequently, as we receive new data from the on-site meters.
Display Energy Certificate
Since 9 January 2013 public buildings in the UK over 500m2 have been required to display a Display Energy Certificate (DEC) prominently at all times. Display Energy Certificates were introduced by the Government in response to the EU Energy Performance of Buildings Directive which all EU member states were required to implement by January 2009.
DECs are designed to promote the improvement of the energy performance of buildings. They are based upon the actual energy performance of a building and increase transparency about the energy efficiency of public buildings. DECs use a scale from A to G with A being the most efficient and G the least. The Display Energy Certificate for Tate Modern is available here or by clicking the plaque on the right.
Tate Modern shares its sustainability data so that everybody can help to identify new savings and suggest improvements. The icons below show the utility data currently available for each year.
If you have ideas on how Tate Modern could use energy more efficiently, please let us know!
How do you calculate the CO2e emissions from a unit of energy used?
Energy retailers and the government produce conversion factors that describe the typical carbon impact of different energy sources. These allow us to take the energy uses (in their respective units), and calculate the approximate carbon dioxide emissions, normally measured in kilograms of carbon dioxide equivalents (kgCO2e). Defra's UK conversion factors may be found at Defra's 2011 Guidelines. For Tate, carbon conversion factors of grid electricity are based on the carbon factors from Tate's energy utility provider. The factors in use are 0.48234 per kWh for electricity.
How do you get these data from the buildings?
Getting these energy data out of some buildings is harder than others, but in general the buildings contain a small low-power computer which takes very frequent readings from the electricity meters and stores the data. Every few seconds, this computer sends the information it has collected to a server. Your browser will then ask this server for the data it needs in order to draw the real-time detailed graphs and website teasers. The energy impact of this process is very low, and it gets lower with each additional site that uses the system. Data acquisition at Tate Modern is through third party systems that connect directly to the fiscal meters on the site. These collect performance data for each full half hour, and do not show any detail within each half-hour period. The systems introduce a delay that means we cannot show the energy data until the day after they have happened (this pattern is called, in the energy industry, 'day plus one' data.
What do the colours on the graph mean?
For buildings, the colours in the graph show approximately how the current level of usage would lead to a given Operational Rating – as set out on a Display Energy Certificate (DEC) – if the performance for a given moment carried on for an entire year. This goes from dark green for ‘A’ to red for ‘G’. We calibrate this using input data used for generating the building’s DEC, together with information relating to 'normal' buildings of its type. If we do not have data for all of the utilities noted in the DEC then the graph will appear in bluescale, to indicate that the usage displayed on the graph is not representative of the full energy use of this building. Graphs for communities show in bluescale.
Why are you using these units and what do they mean?
We provide three different measures of the energy used: the amount of energy, its monetary cost, and the carbon impact of the energy used. Energy use is measured in kilowatt hours (kWh), which are the standard units of a home energy bill (1kWh is the amount of electricity used by ten 100W light bulbs in one hour). For electricity this number represents the amount of energy that flows into a building through the meter, and excludes distribution losses. For gas it is the amount of energy that is theoretically available by burning all the gas in an imaginary burner. For district heating it reflects a flow of temperature into the building over time (after the heat produced by burning the fuel has been transported to the meter, which involves other losses). So these numbers, while all being measured in kWh, mean very different things. This is one reason that we prefer to use 'units per hour' when combining them. In some ways it would be better not to combine them at all, because it implies that the measures are comparable. This is a global challenge though, and conventions have become established around combining kWh. So we'll have to fix it another day. Monetary cost is calculated using the costs per 'unit' for each utility in every building. The figures used are noted below in the Notes section. The carbon impact is measured in kg of CO2e (the e stands for equivalent) which takes other climate-affecting gasses into account besides carbon dioxide.
How much does this organisation pay for its energy?
Prices come from the latest energy bills for Tate, which for electricity average out at 7.98p per unit.
Where does the image come from?
The photograph of Tate Modern above is © Tate Photography