Data center real estate runs on a handful of terms that sound exact and aren't. Most have no legal definition, so two people can use the same word for two different things. This page gives the meaning we use, says where a term is only industry habit, and points to the source when a regulator or a market report has defined it.
Land and buildings
Powered land
Land or a site where electricity at industrial scale is available, reserved or agreed with the grid operator. There's no legal definition, and the phrase covers everything from a plot near a substation to a site with a connection of a known size agreed for a known date. What it means in Norway, Sweden and Finland, where the operator's own records can be checked, is in our piece on powered land in the Nordics.
Powered shell
A finished building shell with the power connection in place, with the inside left for the tenant to fit out. That's how we use it. CBRE's Q2 2026 report on European data centres describes shell space as a wind and watertight structure with exposed slabs and finishes, where the landlord obtains the permissions for data center use and an incoming diverse raw high-voltage supply would usually be provided. CBRE doesn't define "powered shell" as a term of its own, so where the line sits between a shell and a powered shell is a question for the contract.
Powered land versus powered shell
Powered land has no building on it. A powered shell does. Both promise power, and neither promise means much until you know whose name the connection is in and on what terms.
Build to suit
A hall designed and built around one customer's load and schedule, rather than a ready-made one. CBRE's definitions note that wholesale operators typically sell shell space that is then built out to suit the customer, and that the landlord may supply the chillers and back-up power equipment on a build-to-suit basis.
Fitted space
Space that's ready for the tenant's IT equipment almost immediately, or after minor works for bespoke equipment and layouts. That's CBRE's wording. Retail colocation, in the same report, covers fitted space only. Wholesale covers both fitted and shell space.
White space
The floor area where the IT equipment goes: racks, cabinets and the cabling around them. It can be quoted in floor area or in the power it can carry. We haven't found a standard definition, and sources differ at the edges, so the useful question is what a quoted figure includes.
Take-up, availability and vacancy
Three market measures that get mixed up. In CBRE's definitions, take-up is the capacity sold in a quarter. Availability is the capacity vacant and available to sell, and the vacancy rate is availability as a percentage of total supply. Capacity that will only count as supply later is called pre-leased.
FLAP-D
Frankfurt, London, Amsterdam, Paris and Dublin: the five largest colocation markets in Europe, as CBRE uses the term. "Rest of Europe" is everything else.
The grid
Reservation and capacity queue
In Norway, a request that the grid company judges mature gets either a reservation or a place in a capacity queue, based on the date the applicant submitted sufficient documentation. Keeping either one takes sufficient progress on the project, and the regulation has it withdrawn, after advance notice, if the project departs significantly from its maturity criteria for reasons that are the customer's responsibility or risk. Statnett describes the queue the same way: when mature orders exceed the capacity available, the rest wait, and their place is set by the time of the order.
Maturity assessment
A test the grid company applies to a connection request before it reserves anything. In Norway it has been a duty for larger requests since 1 January 2025. The regulation lists the minimum criteria, which include a binding progress plan and the status of permits and agreements, and the grid company has to publish them in writing. Statnett set tougher requirements for the largest requests in June 2026, stated to apply from 1 July 2026.
First come, first served, and first ready, first served
Statnett calls first come, first served the main rule of its connection process. The European Commission's guidance on grid connections, part of the European Grids Package presented on 10 December 2025, recommends applying first ready, first served, with transparent maturity criteria and regular monitoring of connection queues. Svenska kraftnät's proposal of May 2026 uses the same idea for capacity zones: a competition on who is ready first.
Construction contribution
A payment towards grid work that more than one customer may use. In Norway the customer commits to covering all or part of the project development costs before getting a reservation, signs an agreement on construction contributions when building starts, and Statnett collects a contribution from other customers who connect to the same facilities or increase their capacity there, an obligation that lasts ten years from the first customer's connection. See powered land in the Nordics for where that sits in a reservation.
Connection agreement
The contract between the customer and the grid company. At Fingrid in Finland it takes effect when both parties have signed it and the customer has paid the connection fee. A letter of intent doesn't reserve any grid connection capacity, in Fingrid's own words.
Firm, non-firm and conditional
A firm connection has no agreed conditions for cutting the load. A non-firm one does. "Conditional" can mean either that, or something about permits, depending on the country. We've given that its own page: firm and non-firm grid connections.
Quick answers
What's the difference between powered land and a powered shell?
Powered land is a site with power and no building on it. A powered shell is a finished building shell with the power connection in place and the inside left to fit out. They're market terms, and contracts differ on what they include.
What is white space in a data center?
The floor area where the IT equipment goes: racks, cabinets and the cabling around them. It can be quoted in floor area or in the power it can carry, and we haven't found a standard that fixes what a figure includes.
What does build to suit mean?
A hall designed and built around one customer's load and schedule, rather than a ready-made one. CBRE notes that wholesale operators typically sell shell space that is built out to suit the customer.
Is a grid reservation the same as a connection agreement?
No. A reservation holds capacity for a project while it keeps moving. A connection agreement is the contract with the grid company, and at Fingrid it takes effect once both sides have signed and the fee has been paid.
Related: The Nordic Grids Side by Side, firm and non-firm connections and how we work on land development.
Sources
All pages opened and read on 17 October 2026.
- CBRE Research, "Europe Data Centres Figures", Q2 2026, definitions page: supply, availability, vacancy, take-up, pre-leased, FLAPD, shell and fitted space, retail and wholesale colocation, build to suit. cbre.com
- Statnett, "When grid companies and direct customers are going to connect to the power grid" (English, last updated 20.12.2024): first come, first served, capacity queue, construction contributions, ten-year obligation. statnett.no
- Lovdata, Forskrift om nettregulering og energimarkedet (NEM), FOR-2019-10-24-1413, § 3-4 (maturity assessment, reservation or queue place by date of sufficient documentation, progress, withdrawal; in force 1 January 2025). lovdata.no
- European Commission, "European grids" (energy.ec.europa.eu): European Grids Package presented on 10 December 2025; guidance C/2025/8473 on efficient and timely grid connections, first-ready first-served. europa.eu
- Svenska kraftnät, webinar on the government assignment on the connection process, 26 May 2026: proposed capacity zones by customer type and a "ready first" competition. svk.se
- Fingrid, "Connection agreement and grid connection fees": agreement takes effect when signed and the fee is paid. Fingrid, "Connection to the main grid": a letter of intent does not reserve grid connection capacity. fingrid.fi
- Statnett, "Modenhetskrav for forbrukstilknytninger", June 2026 (listed on Statnett's consultation page as "gjeldende fra 1.07.2026"): stricter maturity requirements for the largest consumption requests. statnett.no
General information, not legal advice. Terms marked as our usage are not standard definitions. Rules and pages as read on 17 October 2026.