In richer countries it is usually electricity or fossil fuels. In poorer countries it is usually wood.
electricity
In a developing country, biomass is most likely to be used for cooking and heating purposes. This can involve burning wood, crop residues, animal dung, or charcoal for energy. Biomass is often a primary energy source in areas with limited access to modern fuels and technologies.
Biomass is still a major source of energy in many developing countries, particularly in rural areas where access to modern energy sources is limited. In countries like India, China, and parts of Africa, biomass is used for cooking, heating, and other energy needs. Additionally, some developed countries, such as Sweden and Finland, utilize biomass for electricity generation and district heating.
Vitamin C from any source can get destroyed in the process of cooking.
wood
Approximately 10% of the world's population uses biomass as their primary source of energy for cooking and heating. This reliance on biomass can have significant health and environmental impacts due to indoor air pollution and deforestation.
The auxiliary heat in your heating system comes on when the primary heat source, such as a heat pump, is unable to meet the desired temperature setting. This usually happens during very cold weather or when the primary heat source is not functioning efficiently. The auxiliary heat helps to supplement the primary heat source and maintain a comfortable temperature in your home.
This is true, and also for heating the earth's surface and the oceans. The only other source is the heat from the centre of the earth. Man-made activities are small by comparison.
The major source of energy in the US during the late 1700s to mid-1800s was wood. With abundant forests, wood was used for heating homes, cooking, and powering early industrial processes before coal began to take over as the primary energy source.
The first renewable energy source used by humans was likely wood, as it was used for heating and cooking thousands of years ago.
Heating oil currently serves about 23 million Americans in 8.6 million households.
The Sun is Earth's primary source of light energy. It emits light in the form of electromagnetic radiation that reaches Earth and provides energy for various processes such as photosynthesis and heating the planet.