Fossil fuels, such as coal, oil, and natural gas, are non-renewable energy sources derived from the remains of ancient plants and animals. They release harmful emissions when burned, contributing to climate change.

Retrofitting involves modifying existing buildings or systems to improve their energy efficiency. This can include adding insulation, upgrading windows, or installing energy-efficient appliances.

Combined Heat and Power (CHP) systems generate electricity and heat simultaneously, maximizing energy efficiency and reducing waste. They are often used in industrial and commercial settings.

Energy-efficient lighting systems, such as LED bulbs, consume significantly less energy compared to traditional incandescent bulbs, resulting in lower electricity bills and a reduced carbon footprint.

Smart grids incorporate advanced technologies to efficiently manage electricity flow and integrate renewable energy sources. Fossil fuel power plants are not typically considered a component of smart grids due to their reliance on non-renewable fuels.

Peak demand refers to the highest level of electricity consumption within a defined time interval, typically a day or a season. Managing peak demand is crucial for grid stability and efficient energy distribution.

Geothermal heat pumps extract heat from the earth's subsurface during winter and release it into the building, and vice versa during summer, providing efficient heating and cooling.

Energy-efficient appliances consume less energy to perform the same tasks as conventional appliances, leading to lower energy bills and a reduced environmental impact.

Adopting energy-saving technologies generally leads to reduced energy consumption and lower energy bills. Higher energy costs are not a benefit of energy-saving technologies.

Smart thermostats allow users to program heating and cooling schedules based on their daily routines and preferences, optimizing energy usage and reducing energy waste.

While intermittency, cost, and grid infrastructure are challenges, overproduction of renewable energy is not typically a concern, as excess energy can be stored or exported to other regions.

Energy conservation policies aim to encourage the adoption of energy-efficient technologies and practices, leading to reduced energy consumption and a more sustainable energy system.

Incandescent bulbs are traditional lighting technology known for their low energy efficiency. CFLs, LEDs, and halogen lamps are more energy-efficient alternatives.

Energy-efficient windows are designed to minimize heat loss during winter and heat gain during summer, resulting in lower energy consumption for heating and cooling.

Fossil fuel-based power generation is not considered a key component of a sustainable energy system due to its reliance on non-renewable resources and its contribution to greenhouse gas emissions.