Out to Sea: Wind Turbines and the Ocean Breeze
Wind energy has been used for more than two thousand years. Since its discovery, wind energy has been crucial to farmers and ranchers that use windmills for pumping water and grinding grain. Today wind energy is mostly used to generate electricity through the use of turbines. The need for environmentally safe renewable energy has led engineers to research and develop large-scale wind farms. The very first offshore wind farm was installed off the coast of Denmark in 1991. Since that time, commercial-scale offshore facilities have been operating in shallow waters around the world. Offshore winds tend to blow harder and more consistently than on land with the highest wind speeds occurring further out to sea and at greater depths. The current bottom fixed offshore turbines, with foundations in the seabed, have depth restraints and cannot harness the higher wind speeds found further out to sea.
Harnessing deep sea wind requires engineers to develop new foundations so the turbines can reach greater depths. Turbines must be able to withstand hurricane-force winds, storm waves and in some cases-ice flows. Several construction approaches have been established but there is yet to be a stand out development. To get deep sea platforms up and running quickly, one common strategy has been to build the structures at onshore shipyards. This boosts local economies as well as lowering the cost of production by using local resources. The turbines can then be towed out to deep water and once on location, can then be hooked up to pre-installed mooring chains. A single connection point and power transmission cable allows the platform to be connected and running quickly with little disruption to ocean life.
Seafloor ecosystems have been monitored closely during the whole process of introducing stationary wind turbines to each location’s environment. Current research has determined that the largest impact has been during the construction phase. Stationary turbines use pile driving to install poles into the ocean floor, which causes marine mammals to leave their habitats due to the loud sound pulses. This is remedied by conducting construction on land for the floating turbines which lower environmental effects considerably. Researchers say it’s still too early to draw conclusions but by disturbing the ocean floor less, floating wind turbines will be the go-to for future wind farms.
Creating a New Generation of Solar Cells
For the last few decades, manufacturers have used silicon solar panels for “Green” energy. These panels are relied upon because the material used was the most efficient at converting sunlight into electricity. The current goal in research has been to develop solar power capable of higher efficiency and better practical usage possibilities. To accomplish this, engineers have been researching Organic Solar Cells. While silicone panels produce typically between 5-27% converted sunlight, organics will produce between 15-18%. Here lies the problem. With the large difference in rates, what makes organic solar cells the preferred method for solar panels?
Organic solar cells are considerably more cost effective. Organic photovoltaics can cut the total solar energy system cost significantly. Organic photovoltaics at 15% efficiency over 20 years would produce electricity at 7 cents per kilowatt-hour. In 2018 the national average is 13.8 cents per kilowatt-hour. Creating the Organic solar cells is also less costly than traditional silicon panels. Silicon panels are thick, rigid panels that require extensive installation. The Carbon Organic panels can be built cheaply in rolls of material that are much more flexible.
New materials, design, and processes have a fabrication yield of 95%. That means nearly all devices are created without shorting out which cuts production costs considerably. The organic photovoltaics can be made of compounds that are dissolved in ink, this allows them to be printed on thin rolls of plastic. The Organic cells can then bend or curve around structures. Flexible, printed solar cells have a wide range of possibilities. They could work indoors and can be built into windows. They offer huge potential for many industries since they are lightweight, and can be used on the roofs of cars, in clothing, even built into the screen of your cell phone so it charges while you are out and about.
The industry hopes to develop worldwide applications within the next five years. Soon you will have solar powered camping gear, smart wearables, and even solar-powered cell phones. The future of solar power looks bright.
Thermogalvanic Effect: Harnessing Waste Heat
The discovery of fire was a turning point in human history, it offered portable warmth, light, protection, and a new way of preparing food. It was also one of mankind’s most successful attempts to harness energy. Because energy is almost always lost in the harvesting phase, researchers around the world have spent decades seeking ways to harness this wasted energy.
Researchers at MIT and Stanford have found a new way to transform waste heat into electricity. Electricity is considered high-grade energy because it can be converted into other forms of energy for use and storage without significant losses. Thermal energy is low-grade energy, which means that attempts to transform heat back into other forms of energy is costly and inefficient. Most of the time, thermal energy is written off as waste heat and released into the environment. Converting low-grade energy back into high-grade energy is an uphill battle, but there are new thermoelectric products that could be our best bet. Efficient and low-cost thermal energy-harvesting systems are needed to utilize the tremendous low-grade heat sources.
The new technology uses available materials and could be used to recycle the large amounts of wasted heat generated in industrial processes and electric power plants. The new system allows waste heat to raise the temperature of a battery, and thanks to the thermogalvanic effect, the battery can now be charged at a lower voltage than would normally be required. The battery is then cooled down, and because the charging voltage is lower at high temperatures than at low temperatures, once it has cooled the battery can deliver more electricity than what was used to charge it. That extra energy, of course, does not just appear from nowhere: it comes from the heat that was added to the system.
Imagine the potential of thermoelectric-powered devices, Engineers are working diligently to find the most cost-effective approach and I don’t know about you but just the possibility of charging a cell phone by using body heat is something to look forward to!
The Plastic Strategy
The great plastic debate - not only in politics but also in everyday conversations people are demanding we save the environment. Many argue that the world should do away with all plastic use, which unfortunately is not realistic. Plastic is necessary for highly perishable foods as well as high moisture content products. It is widely known that the plastic consumption of the world is out of control but, if we were to stop using plastics for food, the amount of food spoilage would be over 20-times the waste of the packaging. The creation of new technology is required if we want to do more than just clean up the mountains of plastic waste and hope the next generation is more considerate in their consumer-driven lives.
Despite the challenges related to plastic waste, demand continues to grow. Engineering goals have started to shift toward a new plastic strategy: bioplastics. The traditional biodegradable plastics just are not degrading fast enough to keep up with demand. To understand the difference between the two types of plastics, clarifying the terms will help:
Bio-based plastics are all about renewable raw materials. Renewable raw materials such as sugar, corn, or wheat are used to create the plastic. Polylactic acid (PLA) is a good example: it is a 100% bio-based plastic and today mostly produced from corn. In contrast, biodegradable plastics have been designed to decompose and degrade under the right conditions, for example, when in contact with soil, compost or even water.
Engineers are committed to finding renewables that are still durable, recyclable, and reusable. Already bio-based plastics are being used in car parts, packaging, even children’s toys. The next step engineers are trying to achieve on an industrial scale is using these plastics as a renewable diesel. They are taking waste plastic and turning it back into a raw material for fossil refining. To do so plastics are either chemically or mechanically recycled. Mechanical recycling reduces the plastic into granules, but it cannot be reused for food packaging as there are impurities. Chemical recycling breaks the plastic down into a liquid similar to crude oil. These plastics are free of impurities making this process the optimal choice.
Environmentalists have been raising awareness for a plastic-free future. One such movement is saving sea turtles by switching from plastic straws to paper ones. While filled with good intention this effort completely defeats the purpose. By switching to paper, it requires more trees to be cut down which results in decreased oxygen (that vital substance) needed by every living creature on the planet. The practice of conservation is a good one, and engineers have been hard at work securing a better future by creating a way to reuse the plastics we recycle.
The World's First Seawater and Solar Powered Farm
A state-of-the-art tomato farm has begun operations in Port Augusta, Australia. What makes this farm unique is that it runs completely on seawater and solar power. There are tomatoes growing in the desert! Thanks to the efforts of Sundrop Farms Holdings LTD 37,000 lbs of tomatoes will be on shelves every year. This is paramount since traditional agriculture is wasteful in terms of water and fossil fuels. Instead of soil, pesticides, fossil fuels, and groundwater, Sundrop Farms uses only Solar Power and desalinated seawater on its 49-acre farm.
The increase in population has influenced scientists, researchers, government officials and many other professionals to address food, water, and energy shortages. In this pilot facility, water is pumped from the Spencer Gulf 1.2 miles and then desalinated with solar power. The farm's solar power is generated by 23,000 mirrors that reflect sunlight towards a 377ft high receiving tower. 118 million gallons of fresh water each year, will be created. That’s 180 Olympic sized swimming pools. This process makes it the optimal environment to grow tomatoes. Seawater-soaked cardboard keeps the plants cool and solar heat keeps the greenhouse warm in winter months. The seawater sterilizes the air and plants are grown in coconut husks allowing them to thrive without pesticides.
Extreme weather events make it difficult to consistently provide consumers with products each year. Agriculture in different areas is devastated by weather. One solution to this problem was put to the test last week during a once-in-50-year storm that wreaked havoc in South Australia. Sundrop Farms was able to take the brunt of high winds and continue operations despite a massive blackout that crippled many industries in the areas making them inoperable. While other companies suffered massive setbacks Sundrop Farms is "living proof" that its groundbreaking technology could work on a large scale.
Other solar/seawater farms are being developed from the U.S. to Portugal and Africa. Each company and facility will be fulfilling local needs as well as sculpting the agriculture of tomorrow.