ENVIRONMENTAL SCIENCE
ENERGY
We use energy in all aspects of our lives Electricity - Light, heat, appliance, iPods Oil – heat homes and water Fuel – cars, truck, trains, equipment How was energy used to produce…
Your clothes Your desk Your chips
ENERGY
Much of our energy comes from Fossil Fuels Coal and petroleum (oil) Originated from plants and animals that existed millions of years ago = fossil fuels
Known as non-renewable energy sources Once supply is gone, its gone forever
Are we in an energy crisis?
ENERGY CRISIS Energy Crisis = demand for energy is higher than amount of fuel produced
World demand for energy is rising
US uses 21 million barrels of petroleum per day
US petroleum mainly comes from Middle East We import, not produce it here What if they cut us off?
Petroleum is created from non-renewable resources. What happens if we run out?
ALTERNATIVE ENERGY SOURCES Alternative Energy – any form of energy besides fossil fuels Biofuels – energy sources created from renewable resources such as agriculture crops
Wind Energy – energy created by harnessing wind power
Solar Energy – energy created by harnessing energy from the sun
BIOFUELS Biofuels – energy sources created from renewable resources Renewable energy = can be produced continuously Agricultural crops commonly used 4 Forms of Biofuels:
Ethanol Biodiesel Biomass Methane
BIOFUELS - ETHANOL Ethanol – created through fermentation and
distillation of grain. Illegal whiskey makes made moonshine – this was ethanol Brazilian ethanol made from sugarcane US grains used for production
Corn, sorghum, wheat
40% of US corn crop used for ethanol production E85 – 85% ethanol, 15% gasoline E10 – 10% ethanol, 90% gasoline
Standard fuel when you fill up at the pump
BIOFUELS - BIODIESEL Biodiesel – made by mixing oils from plant
and/or animal sources with petroleum diesel fuel Purpose is to make diesel fuel last longer Common sources:
Used vegetable oil from frying in fast food restaurants Soybean oil
Benefits: renewable resource, less emissions Issues: clogged fuel lines if not cleaned, oil filter must be changed frequently, slight fried food odor
B20: 20% biodiesel, 80% petroleum
BIOFUELS – BIOMASS Biomass – large amounts of organic products used for fuel Direct fuel: burned for energy
Wood, lawn clippings, wood chips, or manure Paper and lumber mills use scrap wood as fuel
Manure is used to power an ethanol plant in Hereford, TX (Cattle Capitol of the World)
BIOFUELS – METHANE Methane – natural gas Natural Gas – created by the transformation of plants and animals into fossil fuels
Benefits: burns clean Issues: difficult to transport, highly flammable
BIOFUEL CONCERNS Can the US produce enough ethanol to be a
serious alternative to gasoline?
High demand for ethanol = high demand for corn = rising corn prices = cost of animal feed rises = cost of food at grocery store rises
Possible lower gas mileage
Possible corrosion of the engine block because of high water content in fuel
What if the crop is affected by drought, disease, insects and yields for the year are low?
Is it wise to grow crops for fuel? Will there be enough to also meet our food supply?
WIND ENERGY
Used for many years to bring water up from deep wells to provide water to people and livestock where there was no electricity (windmills)
“Wind Towers” are more efficient windmills Large propeller blades turn in the wind to power generators that produce electricity
WIND ENERGY CONCERNS Does the wind blow everywhere?
Does the wind blow all the time?
Does the wind always blow at the same speed?
How can wind energy be stored?
SOLAR ENERGY
Most abundant, less exhaustible, and less pollution than any other energy source
2 types of solar energy systems: Active – collects the sun’s energy in the form of heat and stores is for future use
Passive – collects the sun’s energy, but does not store it South-facing solar panels
SOLAR ENERGY CONCERNS How can the sun’s heat be converted to electricity?
What is the best way to store the sun’s heat to use in the dark?
CONVENTIONAL VS. ORGANIC AGRICULTURE
We live in a very wealthy society where we buy nearly everything we consume
People used to grow at least some of the food they ate – garden, chickens and eggs, cows for milk They knew where their food came from and how it was produced
Today, people have no idea!
MODERN AGRICULTURE Today less than 2% of the US population are
farmers and they must feed: Over 300 million people in the US today Nearly 7 billion people in the world
Can that be done using the same farming methods that people used when everyone grew a lot of their own food?
2 types of Modern Agriculture: Conventional farming Organic farming
MODERN AGRICULTURE Conventional Farming –
Food is produced in huge quantities Shipped from where it is produced to where it is consumed Very efficient form of farming
Due to technology advances Equipment Pesticides (Insecticides, Fungicides, Herbicides) GE Crops
Technology allows farmers to produce enough food to feed all America’s and much of the world’s people
MODERN AGRICULTURE There became some concerns…
The USDA regulates how much pesticide residue can be on food Very, very, very tiny amounts are allowed, but are tested for years on
animals and even babies to make sure they are safe
Some people believe that any chemical residue on food is too much Any food produced using pesticides and fertilizers are unhealthy
So we ended up with a new agriculture movement…
MODERN AGRICULTURE Organic Agriculture
Food and fiber are produced using only materials that are “organic”
“Organic” are substances that only occur in nature and did not result from manufacturing
There are many rules and regulations about what can and cannot be used for growing food Many types of pesticides are prohibited Manure may be used for fertilizer if composted properly Hormones and antibiotics are not allowed in animals
So is one system any better than the other???
LET’S COMPARE…
Activity: Have groups or pairs research and present each aspect of conventional vs. organic farming. Have them list practices, advantages, and disadvantages of each
Insect Control Weed Control Fertilizers Animal Housing Animal Feed Animal Hormones Animal Antibiotics Food Safety GMO Foods Environmental Safety Family or Corporate Farms Food Prices Nutrition of food
Use http://findourcommonground.com/, Agriscience text book
MODERN AGRICULTURE
So, Conventional Farming or Organic Farming?
The Bottom Line:
We are all part of the agriculture industry. There is a demand and place for both types of systems, and each system works for its
consumers. Different is not wrong, it is just different. Remember, we are all on the
same team, so let’s support each other.
INTENSIVE PRODUCTION SYSTEMS Systems that produce a large amount of food in a very small area Aquaculture Vertical Farming
AQUACULTURE
Up until the 1970’s, most of the fish sold in the markets were caught from the wild
However, as the world population has increase, more and more fish were caught from the ocean
A few years ago, maximum amount of fish that could be taken from the oceans in a year was reached The ocean cannot produce enough fish and seafood to feed the world
Fish prices were sky-high
AQUACULTURE
Aquaculture systems are fish and seafood farms
Fish and seafood are raised in both natural constructed ponds that have controlled environments Fresh water or salt water systems
Many fish are raised in a very small area
Challenge: the environment must be managed very carefully to provide adequate nutrition, disease control, and physical maintenance to the fish
SHRIMP FARMS IN EAST AFRICA
FRESHWATER TILAPIA FARM
CHANNEL CATFISH FARM
VERTICAL FARMING
By 2050, 80% of the world’s population will live in urban areas
We will need more farmland to grow enough food for over 9 billion people
Since 1982 America has lost over 23 million acres of farmland to development That’s the size of Indiana!
Our farmland is already shrinking – where will that food be grown?
VERTICAL FARMING
One possibility is vertical farming
Vertical Farming – producing food in a skyscraper greenhouse or vertical structure Hydroponics – growing plants in water without soil
Use nutrient solutions, gravel, pebbles
Aeroponics – growing plants in air without soil Roots are sprayed with nutrient solution
VERTICAL FARMING
Advantages: Crops can be produced year-round Controlled environment, so more consistent, predictable yields
Crops would be sold from same building No transportation needed Reduced loss from spoilage or damage
Reduce need for new farmland, so saves natural resources such as forests
Reduce use of fossil fuels because no equipment or machinery is needed for production
VERTICAL FARMING
Disadvantages: May be too expensive –
start-up costs, operation costs, cost of lighting, heating, and powering may not be possible
Pollution: Greenhouse produce produces more greenhouses than field
produce
Large quantities of water with fertilizer and pesticides need a place for disposal
So many plants in one small area could be severely damaged by spread of insects or disease
A Vertical Garden in Singapore
THIS “PINKHOUSE” IN BRYAN, TX GROWS 2.2 MILLION PLANTS UNDER BLUE AND RED LED LIGHTS
Artist rendering of a 177 foot Vertical Garden planned for Sweden
ENVIRONMENTAL LEGISLATION Farm Bill
EPA regulations