Which of the following might be responsible for increasing a building's base electrical load following an audit?

The choice involving the installation of exhaust fans to increase ventilation is correct because when exhaust fans are added to a building's systems, they require electricity to operate. This increased electrical demand contributes directly to the building's base electrical load. Exhaust fans are designed to remove stale air and introduce fresh air, which is essential for maintaining indoor air quality. However, the energy consumption associated with running these fans adds to the total electrical load, especially if they operate continuously or for extended periods.

In contrast, replacing all light bulbs with LEDs is likely to reduce energy consumption and therefore the base load, as LEDs are more energy-efficient. Improving insulation tends to lower the heating load, reducing the need for electrical heating systems and further decreasing energy use. Shutting down non-essential electrical equipment directly reduces the base load instead of increasing it, as it minimizes overall electricity consumption. Consequently, the installation of exhaust fans aligns with an increase in the base load, making it the correct answer in this scenario.