Glossary: data centers, grid power and powered land

By Razvan Toma · Founder & CEO, Ampervia · Last checked 2026-10-12 · Sources linked below

Access and connection permit: In Spain, the permiso de acceso y conexión: the operator’s grant of the right to connect a given load at a given node. Since RDL 7/2026 it carries a CNAE activity code.
Access capacity: The capacity, in MW, a network operator publishes as available at a node for new consumers (demand) or new plants (generation). In Spain it is published per node and compiled by the CNMC. See Spain grid capacity by province.
AI factory: Industry term for data centers built for AI training and inference, with much higher power density per rack than traditional facilities.
AIFM: Alternative investment fund manager, the regulated manager required under EU rules when capital is pooled from investors into a fund.
Autoproducer unit: In Irish rules, on-site or nearby dispatchable generation a data center must provide to cover its demand; required at 100% of MIC for sites of 1–10 MVA.
Behind-the-meter power: Generation on the consumer’s side of the grid meter (on-site gas, solar, batteries) supplying the data center directly.
Brownfield site: Previously developed land, often a closed factory. In Lombardy, brownfield data centers get lower construction charges than greenfield ones.
Capacity reservation guarantee: A deposit or periodic charge a developer pays to hold grid capacity before using it. Spain’s RDL 7/2026 created one for demand permits of 1 kV and above, payable until activity starts.
Capex per MW: Construction cost divided by IT capacity, the standard way to compare data center build costs.
Club deal: A transaction in which a small group of investors invest together, usually through an SPV, instead of through a blind-pool fund.
CNAE code: Spain’s classification of economic activities. Under RDL 7/2026 a demand permit states the CNAE code of the activity it will serve, and the permit lapses if the connected site does not keep that activity for three years.
CNAE lock: Shorthand for the RDL 7/2026 rule tying a Spanish demand permit to its declared activity code, which stops a factory’s permit being reused for a data center.
Co-investment: Investing directly in a specific deal alongside a sponsor or fund, usually on the same terms.
Colocation: A data center that leases space, power and cooling to several customers.
Connection offer: The operator’s formal offer setting the capacity, works, cost and date of a connection. The strongest evidence that a site is powered.
Connection queue: The list of pending connection requests an operator processes. Queue position, not land, often decides when a site can energise.
Distribution grid: The lower-voltage network run by distribution operators (in Spain, distributors such as i-DE, e-distribución or UFD). Most connections of a few to a few tens of MW sit here.
DSO: Distribution system operator: the company running the local lower-voltage grid.
Edge data center: A small facility, often under 5 MW, placed close to users for low latency.
Energisation: The moment a connection is switched on and the site can draw power.
Firm connection: A connection with guaranteed capacity at all times.
FLAP-D: Frankfurt, London, Amsterdam, Paris and Dublin, Europe’s five primary data center markets, all power-constrained. See FLAP-D connection thresholds.
GDV: Gross development value: the expected value of a project once built and let.
Greenfield site: Land never developed before, typically agricultural.
Grid capacity (site): The total power a site may draw from the grid, including cooling and losses. Higher than the IT load; the ratio depends on PUE.
Hyperscale: Very large data centers built by or for the biggest cloud providers, usually tens to hundreds of MW per campus.
IT load: The power drawn by the servers and network equipment, excluding cooling and losses. Data center capacity and prices per MW usually refer to IT MW.
Land option: A contract giving the right, not the obligation, to buy land at an agreed price within a period, so a developer can secure power and permits before buying.
MIC: Maximum import capacity: in Ireland, the contracted maximum a site may draw from the grid. Irish data center rules are tiered by MIC.
MVA: Megavolt-ampere, the unit of apparent power used for connection sizes. Close to MW for planning purposes; connection rules in Berlin, Amsterdam, Dublin and London are set in MVA.
Node: A point on the grid, usually a substation busbar at one voltage, where capacity is published and new connections are made.
Non-firm (flexible) connection: A connection the operator may curtail at times of grid stress, offered sooner than a firm connection. Used in Germany, the UK and Ireland to connect loads earlier.
Powered land: Land with a grid connection, or a secured right to one, large enough for a data center. Its price is driven by the megawatts it can draw, so it is usually quoted per MW rather than per square metre. See What is powered land?
Powered shell: A building with power delivered to it but without the tenant’s fit-out (cooling, racks, internal electrical). A step after powered land.
Pro-rata allocation: Sharing scarce capacity among applicants in proportion to their requests, instead of first come, first served. Used by Frankfurt’s and Berlin’s grid operators.
PUE: Power usage effectiveness: total facility energy divided by IT energy. A PUE of 1.3 means 30% on top of the IT load.
Ready-to-build (RTB): A data center site with land control, a grid connection offer or permit, and the planning permits needed to start construction. See What is a ready-to-build site?
Shovel-ready: Informal synonym for ready-to-build: construction could begin without further permits.
Single authorisation (Italy): The single procedure introduced by Italy’s Decree-Law 21/2026, article 8, covering a data center and its grid connection in one authorisation.
SPV: Special purpose vehicle: a company formed to hold one project, so its investors, debt and risks stay separate. See How SPVs and club deals work.
Substation: A facility that transforms voltage between grid levels. Distance to a substation with spare capacity is one of the first site-selection filters.
Transmission grid: The high-voltage network run by the transmission system operator (Red Eléctrica in Spain, Terna in Italy, RTE in France). Large campuses connect here.
TSO: Transmission system operator: the company running the high-voltage grid of a country or zone.
Will-serve letter: A utility’s written statement that it can supply a site. Common in the US; in Europe the equivalent evidence is a connection offer or permit.

Glossary of data center, grid and powered-land terms

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