California and the Energy Efficiency Directive: The Regime Goes Global
Europe wrote the template, but the regulatory pressure is now global, and two developments make that concrete for anyone building digital infrastructure: California's climate disclosure laws and the European Union's recast Energy Efficiency Directive. Together they close the escape routes a company might have hoped to use, one by extending mandatory disclosure into the United States and the other by targeting data centers specifically.
California passed two laws in 2023 that matter far beyond its borders. Senate Bill 253, the Climate Corporate Data Accountability Act, requires companies doing business in California with annual revenue above one billion dollars to disclose greenhouse gas emissions across all three scopes, including Scope 3. Senate Bill 261 sets a lower threshold, around five hundred million dollars in revenue, and requires biennial reporting on climate-related financial risk, drawing on the framework popularized by the Task Force on Climate-related Financial Disclosures. Because these thresholds capture thousands of large companies that operate nationwide, the practical effect reaches well past California. A firm headquartered in Texas or Virginia that sells into California is caught, and it is not going to keep two separate sets of books. The California floor becomes the national floor.
The SB 253 inclusion of Scope 3 is the aggressive part. Scope 3 is where most of a technology company's emissions actually sit, and it is the hardest to measure because it depends on suppliers. Requiring it, at scale, with phased assurance, forces companies to build supply-chain carbon accounting they may never have attempted. Like CSRD, the California timeline has been contested, softened at the edges, and litigated, and you should expect the implementation dates to keep shifting. The obligation itself has proven durable. My read is that the specific deadlines are the least reliable thing to memorize; the structural fact, that a large company operating in the United States will have to disclose all three scopes, is the reliable one.
The European Union's Energy Efficiency Directive, recast in 2023, comes at the problem from a different angle and is the first major law to name data centers as a category. It sets the Union a binding collective energy-savings target and, crucially for our purposes, obliges data centers above a size threshold, commonly cited around 500 kilowatts of installed IT power, to report standardized information on their energy performance, water usage, waste heat, and use of renewable energy into a European database. This is not an emissions cap; it is a transparency mechanism. But transparency is the mechanism that changes behavior, because once every operator's power usage effectiveness, water usage effectiveness, and waste-heat reuse are visible and comparable, laggards have nowhere to hide and customers can shop on the numbers.
The waste-heat provisions deserve special attention because they connect directly to the second half of this course. The Energy Efficiency Directive establishes an efficiency-first principle and pushes operators to assess whether their reject heat can be delivered to a use, such as a district heating network, rather than dumped to the atmosphere. In several member states the pressure is stronger than a mere assessment. Germany's Energy Efficiency Act, for instance, sets explicit expectations that new data centers reuse a rising share of their waste heat, with targets escalating for facilities coming online later in the decade. This is the point where disclosure law stops being an accounting exercise and starts dictating physical plant design and, therefore, where you can afford to build.
It is worth naming why transparency mechanisms like the Energy Efficiency Directive's database change behavior even without a hard cap, because the point is easy to underestimate. When every operator must report power usage effectiveness, water usage effectiveness, and heat reuse into a common, comparable registry, the numbers become a competitive currency. A prospective cloud customer, itself under CSRD or California disclosure obligations, can read the registry and steer its business toward the efficient operators, because that operator's efficiency flows directly into the customer's own reported Scope 3. Transparency, in other words, recruits the market as an enforcement mechanism. The laggard is not fined; it simply loses deals. My read is that this indirect pressure often moves an industry faster than a prescriptive standard, because it lets customers reward the leaders continuously rather than waiting for a regulator to punish the stragglers.
Stand back and the pattern is clear. Europe requires double-materiality reporting with assurance; California extends three-scope disclosure across the United States; and the Energy Efficiency Directive singles out data centers for operational transparency and heat reuse. No single law is a global mandate, but their overlapping reach means a serious operator faces mandatory, audited, comparable disclosure almost everywhere it wants to build. The rational response is not better public relations. It is to change the inputs, and the inputs are set at the site.