Mildred Dresselhaus and the Story of Cycles of Energy

Mildred “Millie” Dresselhaus is an american physicist who is known as the ‘queen of carbon science’. She was a pioneer in the electronic properties of materials and worked in MIT for over 50 years. Her outstanding work has enabled several renewable energy technologies. Through the story of Mildred Dresselhaus, we’ll explore cycles of energy.

Mildred Dresselhaus was born in 1930, in Brooklyn USA. She received her undergraduate degree at Hunter College in New York in 1951, and was counselled by future Nobel-Prize-winner Rosalyn Yalow to pursue further education in physics. She carried out postgraduate study at the University of Cambridge on a Fulbright Fellowship and Harvard University, where she received her MA from Radcliffe College. She received a PhD from the University of Chicago in 1958 where she studied under Nobel laureate Enrico Fermi. She then spent two years at Cornell University as a postdoc before moving to Lincoln Lab as a staff member.

Dresselhaus was particularly noted for her work on graphite (yes, the stuff in your pencil). Her research helped develop technology based on thin graphite which allow electronics to be “everywhere,” including clothing and smartphones. Dresselhaus had a 57-year career at the Massachusetts Institute of Technology. In 1985, she was appointed the first ever female Institute Professor at MIT. Dresselhaus was awarded the National Medal of Science in 1990 in recognition of her work on electronic properties of materials as well as expanding the opportunities of women in science and engineering. Her discoveries helped pave the way for new types of renewable energy technologies.

Energy and You

Look around you right now as you read this, almost everything around you needs power for it to work. The electrical appliances and lights in your house, the gas or oil being burned to heat your house, the petrol in your family car. They all need energy. Energy causes everything to happen, but we rarely think about where our energy comes from. We get vast majority of our energy from burning fossil fuels like coal, oil and natural gas. These resources come from our earth and are known as non-renewable energy sources. This means that once you burn a piece of coal to produce electricity, you cannot use that piece of coal again, it is non – renewable.

Let’s take a closer look at fossil fuels

So the more we use these non-renewable energy sources, the less we have left for the future. We are running out of non-renewable sources and it’s estimated that by the year 2100 we will have run out completely. Another big reason to replace fossil fuels is climate change. Burning of fossil fuels releases carbon dioxide (CO2) into the atmosphere, which acts like a blanket and heats up our planet.

Renewable Energy Sources

If we want a future for this earth, we need to start using renewable energy sources as a way of creating energy. Renewable energy sources can be used over and over again and will never run out. Think of the Sun, will that ever stop shining in the sky? Will the waves in the ocean ever stop crashing against the coast of Ireland? Will the horrible chilly winds in west Clare ever stop blowing? These resources can be harvested to produce electricity and can replace the harmful fossil fuels. The most effective renewable energy resources we have available to us are summed up in this table.

Energy Type How does it work? Advantages Disadvantages
Wave Waves crash against a turbine, causing it to spin, which then produces electricity Reliable
No pollutants
Low maintenance
Expensive
Could damage marine life
Can be noisy
Varies with wave strength
Solar Solar cells convert sunlight directly into electricity Easy to install No fuel costs
Remote areas can have electricity
Expensive
Weather-dependent
No energy produced at night
Tidal Water flows through a turbine, causing it to spin, which then produces electricity No harm to marine life
No pollutants
Low maintenance
Expensive
Can be noisy
May affect the environment
Biomass Wood chips and sawdust are burned, heat energy creates steam and turns a turbine, creating electricity Fuel sources are cheap
Waste at landfill sites can be used
CO2 is released Trees are cut down
Cost of replanting trees
Wind Wind hits a spinning wind turbine and give it energy, this turns a generator and produces electricity Can be built on agricultural land or at sea.
No fuel costs
Large and noisy
Danger to birds and bats
Wind strength dependant
Expensive
Hydroelectric Water is collected in a reservoir (a dam) which creates high water pressure. The water is pushed through a turbine which spins, generating electricity Water can be stored at the dam Cheap to run
No pollutants given off
Wildlife and environment can be affected
Flooding can occur
Can only be built in certain places
Geothermal Steam is generated inside the earth, rises to the surface and turbines a turbine, generating electricity Heat energy is produced consistently
Can heat water directly
Expensive to build
Pipes can corrode
Can only be built in certain places

As you can see, every type of energy has its own advantages and disadvantages, that need to be taken into account when choosing the best resource. Some countries use a combination of several different alternative energy sources. The aim of using renewable energy sources is to have a sustainable future where our energy is conserved. Conserving energy means that we reduce our energy waste and manage our energy sources wisely.

Here’s a recap of the possible renewable energy sources we could use