Affordable and Clean Energy
- Energy is the dominant contributor to climate change, accounting for around 60 per cent of total
global greenhouse gas emissions
- Hydropower is the largest single renewable electricity source today, providing 16% of world
electricity at competitive prices. It dominates the electricity mix in several countries, developed,
emerging or developing.
- Bioenergy is the single largest renewable energy source today, providing 10% of world primary
energy supply.
- 3 billion people rely on wood, coal, charcoal or animal waste for cooking and heating, that could
increase the CO2 emission.
Targets:
7.1 Universal Access to Modern Energy
7.2 Increase Global Percentage of Renewable Energy
7.3 Double the Improvement in Energy Efficiency
7.4 Promote Access to Research, Technology, and Investments in Clean Energy
7.5 Expand and Upgrade Energy Services for Developing Countries
Modern energy examples: Solar, wind, hydropower, geothermal, biofuels, natural gas, coal, petroleum,
uranium.
Why we need renewable energies?
= Unusable crops basically burned and built carbon dioxide and methanes, that could worsening
the climate change.
Most of the humans use:
Petroleum: For fuel
Natural gas: Heat and electricity
Coal: Electricity
Renewable Energies:
1. Solar -> capturing radiant energy from sunlight and converting it into heat, electricity, or hot
water.
- Photovoltaic (PV) systems can convert direct sunlight into electricity through the use of solar
cells.
Benefits: Sunlight is functionally endless.
Current Limitations: Tends to be a significant upfront cost and is an unrealistic expenses for most
households.
Example: Solar panels
How do solar panels work: https://youtu.be/xKxrkht7CpY?feature=shared
2. Wind -> the energy of wind flow by using turbines and converting it into electricity.
Benefits: Clean energy source, which means that it doesn’t pollute the air like other forms of
energy.
Current Limitations: Since wind farms tend to be built in rural or remote areas, they are usually
far from bustling cities where the electricity is needed most.
Example: Turbin
How do turbins work: https://www.youtube.com/watch?v=gE6A5V9qkdQ
3. Hydroelectric -> Water flows through the dam’s turbines to produce electricity (known as
pumped-storage hydropower).
Benefits: Very versatile and can be generated using both large scale projects, like the Hoover
Dam, and small scale projects like underwater turbines and lower dams on small rivers and
streams.
Current limitations: Most U.S. hydroelectricity facilities use more energy than they are able to
produce for consumption, disrupts waterways and negatively affects the animals that live in
them, changing water levels, currents, and migration paths for many fish and other freshwater
ecosystems.
4. Geothermal -> heat that is trapped beneath the earth’s crust from the formation of the Earth 4.5
billion years ago and from radioactive decay (such as volcanic eruptions and geysers). To produce
geothermal energy, it could be by using steam that comes from the heated water pumping
below the surface, which then rises to the top and can be used to operate a turbine.
Benefits: Not as common as other types of renewable energy sources, but it has a significant
potential for energy supply.
Current limitations: Not only is it costly to build the infrastructure, but another major concern is
its vulnerability to earthquakes in certain regions of the world.
Example: Geothermal Heat Pump
5. Ocean -> The ocean can produce two types of energy: thermal (relies on warm water surface
temperatures to generate energy through a variety of different systems) and mechanical (uses
the ebbs and flows of the tides to generate energy, which is created by the earth’s rotation and
gravity from the moon).
Benefits: Predictable, it’s easy to estimate the amount of energy that will be produced, and
abundant.
Current limitations: Those who live in landlocked states won’t have ready access to this energy,
large machinery needs to be built nearby to help capture this form energy, which can cause
disruptions to the ocean floor and the sea life that habitats it, when bad weather comes it
disrupts.
6. Hydrogen -> Hydrogen needs to be combined with other elements, such as oxygen to make
water as it does not occur naturally as a gas on its own. When hydrogen is separated from
another element it can be used for both fuel and electricity.
Benefits: Can be used for as a clean burning fuel, full cells that are similar to batteries, powering
an electric motor.
Current limitations: Since hydrogen needs energy to be produced, it is inefficient when it comes
to preventing pollution.
7. Biomass -> Biomass is organic matter that comes from recently living plants and organisms.
Ex: Plants, wood, and waste (biomass feedstocks).
- Biomass contains energy first derived from the sun: Plants absorb the sun’s energy through
photosynthesis, and convert carbon dioxide and water into nutrients (carbohydrates). The
energy from these organisms can be transformed into usable energy through direct and indirect
means. Biomass can be burned to create heat (direct), converted into electricity (direct), or
processed into biofuel (indirect).
- Biomass can be burned by thermal conversion and used for energy (bioenergy) -> involves
heating the biomass feedstock in order to burn, dehydrate, or stabilize it.
Thermochemical Conversion via Gasification: https://youtu.be/kI7s6IRpOHA?feature=shared
Gasification: Convert biomass to fuels with the process of syngas, using heat
Thermochemical Conversion via Pyrolysis: https://youtu.be/IvZFfx7XhQE?feature=shared
Pyrolysis: Uses heat to decompose biomass in the absence of oxygen.
Biochemical Conversion of Biomass to Biofuels: https://youtu.be/ziYKhp3Clm0
- Biomass and biofuel are a part of the bioenergy. Biofuel exists when biomasses are decomposed.
Benefits: The use of biomass in energy production creates carbon dioxide that is put into the air,
but the regeneration of plants consumes the same amount of carbon dioxide, which is said to
create a balanced atmosphere.
Current limitations: Plants take time to grow.
- The U.S. energy market provides a range of services and products with green energy, also called
green power, being a small category within these options. According to the Environmental
Protection Agency (EPA), green energy provides the highest environmental benefit and includes
power produced by solar, wind, geothermal, biogas, low-impact hydroelectric, and certain
eligible biomass sources.
The data of energy problems: https://ourworldindata.org/worlds-energy-problem
How to jump-start the renewable energy transition:
1. Make renewable energy technology a global public good
2. Improve global access to components and raw materials
3. Level the playing field for renewable energy technologies
4. Shift energy subsidies from fossil fuels to renewable energy
5. Triple investments in renewables
At least $4 trillion a year needs to be invested in renewable energy until 2030 – including
investments in technology and infrastructure – to allow us to reach net-zero emissions by 2050.
6. Ride a bicycle (transportation)
7. Plant trees
8. Implement solar power in your life, such as battery chargers, solar-powered water heaters, mini
fridges, tablets, lights and flashlights
9. Replace your electric security and garden lighting with solar powered lights.
10. Invest in a reusable glass drinking bottle and fill it from the tap.
Producing bottled water uses petroleum and natural gas resources at 2,000 times the rate of
delivering clean drinking water to a tap.
Bottled and tinned soft drinks cost us even more.
11. Recycling.
12. Use what nature gave you.
13. Residential uses of energy.
Organizations:
1. UNEP (UN Environment Programme)
2. IEA (International Energy Agency)
