Carbon intensity update for 23rd Sep 25

On September 23, 2025, the UK’s carbon intensity fluctuated significantly throughout the day, reflecting changes in electricity demand and the availability of renewable energy sources. At Jaxi, we believe that staying informed about carbon intensity can help consumers make smarter decisions about when to use energy-intensive appliances, supporting a greener, more sustainable future.

Carbon Intensity Breakdown for September 23, 2025

Midnight to Morning (00:00 – 09:00)

• Carbon intensity began at moderate levels, ranging between 159 to 171 gCO₂/kWh through the night until 4 AM.
• From 4 AM to 9 AM, as morning routines kicked in, emissions rose into the high range, peaking at 214 gCO₂/kWh.

Late Morning to Afternoon (09:00 – 15:00)

• The intensity dipped back to moderate levels during the late morning, reaching a low of 136 gCO₂/kWh around 11:30 AM.
• By 3 PM, demand increased again, pushing levels to 193 gCO₂/kWh.

Evening Peak (15:00 – 21:00)

• This was the period of highest emissions, as expected during peak household usage after work hours.
• The carbon intensity peaked at 229 gCO₂/kWh around 6 PM, before starting to ease after 7 PM.

Nighttime (21:00 – 23:00)

• By late evening, emissions dropped once more to moderate levels, ending the day at 157 gCO₂/kWh.

Key Takeaways for Energy Efficiency

The data highlights two critical periods for managing your energy use:

• Low carbon intensity window: Late morning, particularly around 11:30 AM, is an ideal time for running high-energy appliances like dishwashers or washing machines when emissions are lower.
• High carbon intensity window: Evening, especially around 6 PM, saw peak emissions due to increased electricity demand. If possible, try to avoid using energy-heavy devices during this timeframe.

When demand surges and renewables can’t meet the load, generators often have to rely on fossil fuels like coal, which significantly increases carbon intensity. At Jaxi, we encourage households and businesses to monitor live carbon intensity data and shift appliance usage to times when cleaner energy is available.

Every small change adds up. By syncing your energy consumption with greener grid periods, you contribute to reducing overall emissions and building a cleaner energy system for everyone.

Data Source: National Grid UK