IHD — International Horizon Development

Guides

In-depth guides

Schemes explained in depth: how they work, who is involved, timelines and pitfalls, backed by the official texts. Each guide is updated when the regulation changes.

Engineering office in Madrid at blue hour: energy efficiency files, a laptop showing a savings chart and plans of an industrial building, in front of the lit city.

Energy regulation

CAE sujeto delegado: who does what in Spain

Sujeto obligado, sujeto delegado, verificador, Gestor Autonómico: the roles in Spain's CAE system and the accreditation conditions for the delegate.

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A large industrial workshop at blue hour: cylindrical destratification fans hang beneath the steel roof structure, above a lit concrete floor and workstations.

Energy regulation

Air destratification fans: when to install them

Eligible buildings, exclusions, requirements and kWh cumac amounts under the French CEE sheets BAT-TH-142 and IND-BA-110: a guide to air destratification.

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Rooftops of a Spanish city at blue hour, with an air-to-water heat pump and solar thermal collectors on the terrace of a renovated apartment building

Energy regulation

Spanish CAE scheme: parties, steps and 2026 duty

How Spain's CAE energy savings certificates work under Real Decreto 36/2023: parties, steps, deadlines, thresholds, the 2026 obligation and the sujeto delegado.

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A European neighbourhood seen from a rooftop at blue hour, with renovated buildings with insulated facades, heat pumps on the roofs and a lit industrial area in the distance.

Energy regulation

Energy savings obligations in Europe

What Article 8 of Directive (EU) 2023/1791 requires until 2030, the two routes open to Member States, and the examples of France and Italy.

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Collective air-to-water heat pumps installed on the roof of a residential building at blue hour, connected by insulated pipework, with the lit city in the background.

Energy regulation

Sizing a collective heat pump

What CEE sheets BAR-TH-179 and BAT-TH-163 require to size a collective air-to-water heat pump: prior study, Etas, design temperature.

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