Traditional switch to winter time takes place in the early hours of Saturday, October 28, through Sunday, October 29, as clocks are turned back by one hour, returning from 03:00 to 02:00. The change is often discussed in terms of energy savings, yet experts describe the effect as controversial and modest when it comes to actual consumption.
Experts note that although the clock change is a heated topic, the energy savings from adjusting the clock can create a false impression of real reductions in energy use. The Institute for Energy Diversification and Conservation (IDAE) outlines that the potential savings in lighting could reach up to five percent if accompanied by rational behavior and the adoption of lighting-saving technologies.
Time change has roots going back to the oil crisis era of 1974, when some countries moved clocks forward to maximize daylight and cut electricity use. The measure spread across the European Union because it was believed that stable scheduling benefited critical sectors such as transport, communications, and other industries that rely on predictable programming. As a result, European nations adjusted their clocks on the last Sunday of March and the last Sunday of October each year.
Energy calculation
IDAE estimates that the energy savings realized in previous months from earlier summer programs could represent around five percent of electricity consumption related to lighting. This translates to roughly 300 million euros in savings. From that figure, the calculation suggests the potential impact on about 90 million Spanish homes, equating to around six euros saved per household. The remaining savings would be realized in commercial buildings and the industrial sector. It is important to note that these figures are indicative, as IDAE has not updated them in many years and has not indicated plans for regular increases in electricity rates. A rise in the number of homes over recent years also factors into the overall picture.
IDAE stresses that these numbers are potential rather than guaranteed. Realizing the savings hinges on households adopting rational energy use and on the deployment of lighting-saving technologies in commercial buildings and factories. In the same communication, IDAE provides practical tips for reducing energy use in heating. A notable suggestion is to seal gaps and apply adhesives around doors and windows, which can yield five to ten percent energy savings.
Additional recommendations from the official agency include turning down heating at night or when leaving home for extended periods, and considering double glazing to improve insulation. These measures can contribute to substantial energy reductions across households and businesses alike.
At the core, the conversation centers on whether clock changes truly translate into meaningful energy benefits or whether modernization and behavioral shifts in energy use play a larger role. The discussion continues as governments and energy authorities weigh policy options against real-world consumption patterns. Marked citations indicate the source of these insights and projections regarding potential savings and practical steps for households and industries to harness them.