Draw conclusions about the process of harnessing hydropower energy.

Student Journal

Guide - Simple Machines and Linkages

Learn about the various mechanical inventions for laborious tasks, eventually turning and utilising running water sources as renewable hydropower for a community. Create a mill by simulating a historical invention. Pour water over the wheel, where water can be collected and reused to power the movement.

#### Lesson Structure

In each section, the learning objectives are:

* **Warm-up** – Recognise that inventors solve problems to
  improve the world.
* **Imagine** – Explain how the iterative nature of design aims
  to continually improve human life using the example of the
  watermill invention.
* **Create** – Experiment with friction to create a mechanical
  invention that spins in water.
* **Build** – Build a water-powered mechanical invention to
  propel a grindstone.
* **Reflect** – Reflect on potential inventions such as the
  waterwheel to solve big problems in the world and how to improve
  hydropower with water conservation efforts.
* **Challenges** – Extend water-related prototypes through
  open-ended challenges that link to Sustainable Development Goals.

After this lesson, students will be able to:

* Explain the importance of inventions and inventing in human society.
* Explore old mechanical innovations using water power as a renewable energy source for laborious tasks.
* Evaluate the advantages and disadvantages of hydroelectric power.
* Experiment with friction to create a spinning machine to move a structure to simulate a grindstone for grain.
* Invent a design to address the Sustainable Development Goals.

Teacher Notes

Overview and Objectives

Materials

Facilitation and Collaboration Work

#### Teachers: Preparing Your Students (35-60 min)

When students begin the lesson, they start in [Overview and Objectives](#overview-and-objectives), then transition to this [Preparation](#preparation) section. Presented in their view is a vocabulary list of terms and infographics illustrating concepts across STEAM domains throughout this entire lesson.

There are extra guides and optional short intro lessons for preparing student readiness for their first engagement of new terms and content knowledge. Print or distribute the student journal and guides digitally. 
* Review Sustainable Development Goals (SDGs). (5 minutes)
* Read through the vocabulary list. (5 minutes)
* Review the six simple machines. Download the optional asset and share it with students. (10 minutes)
* (Optional) Pick shorter introductory lessons to supplement the guides further. Assign lessons to students and start. (25 minutes)
* Set up an environment for running and reusing water. (15 minutes)
#### Water Source

The water wheel moves with continuously flowing water. Place the project in a plastic bin and pour a jug with water. Then, refill the jug with water poured from the plastic bucket and retry the process.

#### Sustainable Development Goals

Review the [Sustainable Development Goals (SDGs)](https://sdgs.un.org/goals) blueprint based on global needs to create a more sustainable world by 2030 before starting the lesson. (5 minutes)

Student journal

#### Vocabulary (5 minutes)

This is the list of vocabulary terms used throughout the lesson. They will be in **bold** and the definition listed throughout the different sections and in **Student Journal** asset. Students can always revisit the vocabulary definitions with media and questions in the lesson. (5 minutes)

#### Simple Machines and Linkages (10 minutes)

Review the six simple machines. An optional guide can be printed
or shared online with students before engaging in this lesson.
Each simple machine is designed to make work easier or more
efficient and is referenced in this lesson. Download the optional
guide. (10 min)

### Optional Intro Lesson (25 minutes)

(Optional) Pick an introductory lesson to use with guide. **Students won't see these unless assigned to them by you.** (25 minutes)

Preparation

### Facilitation and Collaboration Work

Students can read and answer questions independently or as a group.

#### Inventing by Accident 

Throughout history, people have invented to solve problems and make something about the world better. Inventions range from the wheel and ancient **irrigation** methods to batteries, the internet, and smartphones. Some discoveries have taken many years, others have been discovered by accident, and other inventions resulted from something people thought was a failure!

* Stephanie Kwolek was the chemist who invented Kevlar, a strong fabric that can stop bullets! Her invention was discovered by accident. When attempting to make a substitute for steel in cars, one of the experiments failed. However, Kwolek was still curious about the liquid she accidentally made, and upon studying it closely, noticed that the fibres in the liquid had unusual strength, five times stronger than steel! This incredibly strong, thick, and durable fibre is now utilised in products such as bicycle tyres and vehicle tyres. Kevlar is included in these designs to prevent punctures or holes in the tires. In addition, Kevlar is used in protective sportswear, such as fencing outfits and motorcycle racing gear.
    
* Henry Fleming, the scientist who discovered penicillin, the first antibiotic, discovered it accidentally. He was studying a common bacteria, and after leaving the petri dish near an open window, mould started growing on the dish. Juice from the mould killed the bacteria! His discovery has saved millions of lives.

#### New Uses for Common Items

Sometimes, inventors think of new uses for everyday items or deconstruct household products to improve or create something new.
* Many people know George Washington Carver as a man who invented 300 uses for peanuts. From a very early age, Carver showed an interest in and a talent for plants, medicines, and ways to improve soil and plant production. Carver continued his studies with a Bachelor of Science and a Master of Agriculture and then began teaching farmers how to improve their crops. Some of his improvements were using swamp muck as a natural fertiliser, feeding hogs acorns instead of having to buy feed, and teaching farmers to rotate crops to add nutrients back into the soil. Farmers were suddenly producing an abundance of peanuts through **crop rotation** and needed a market for this crop. As an advocate for these farmers, Carver invented many uses for peanuts, including peanut oil, Worcestershire sauce, paper, soap, and cosmetics.
* Leonardo Da Vinci lived in the 15th century and combined a love of sketching, observation, science, and technology in his inventions. Da Vinci **decomposed** machines of their parts and reimagined them into different inventions, such as a flying machine, a helicopter, a parachute, and scuba gear. While he made some of his ideas, such as a revolving movable bridge for an army, most of his inventions would only be made hundreds of years later.
* Kids have invented many great ideas that we use today! 11-year-old Frank Epperson developed frozen ice lollies, George Nissan created the trampoline at the age of 16, and Chester Greenwood designed earmuffs at the age of 15.

Warm-up

#### Power from Water

Societies have harnessed the power of water for millennia through the relatively simple invention of the water wheel. This invention is on par with other ancient inventions like the ramp, and the wheel, because of how it transformed society. Previous to the waterwheel and mill invention, people had to grind grain by hand, which was a very **laborious** process, but the invention of the water wheel and mill allowed civilizations to grind grains in bulk, and feed a larger population. 

 There were two early types of water wheel, the undershot wheel and the overshot wheel. Water from a river flowed under an undershot wheel and turned it upward. In an overshot wheel, the stream or river was above the water wheel and poured down on top of the paddles, propelling them downward. The energy of the water turned the paddles, which turned the axle of the wheel.

In an undershot wheel, water must flow very rapidly in order to generate sufficient power. In an overshot water wheel, people may have dammed a pond in order to provide an elevated water flow. Gravity exerts a force to pull the water downward, causing it to hit the wheel with greater momentum, thus generating more power.

#### Milling Grain

The Romans improved upon the water wheel design to grind or mill flour as early as the 4th century AD. In order to do this, another smaller wheel, 1/4th the size of the large water wheel connected to the axle of the water wheel. This smaller wheel or gear was also positioned vertically, but it interlocked with another horizontal gear. The horizontal gear turned a vertical axle called a stone spindle. This stone spindle turned a large millstone on top of another millstone. Grain poured down a chute into the millstones to be ground. The millstones were covered in order to keep the flour from flying out everywhere. Instead, flour would be collected in a small opening to one side of the millstones.   

Farmers needed mills in order to convert the wheat and corn they grew into flour or meal to be eaten. A miller would set the stones at different distances apart depending on what type of crop was being ground. There were deep grooves cut into the millstones which broke apart the grains to grind them into flour. Mills were also gathering places for people in the community to visit together while the miller was grinding their crop. Running a mill was a very important job that required constant maintenance. For example, the wooden spokes on the gears would sometimes break off, and a miller would need to fashion new ones to replace the old ones. In addition, the grooves on the stones wore down and had to be rehammered every few weeks. In the process of hammering the stones, tiny bits of rock sprayed up into the miller’s hands. Besides grinding grain, water wheels powered sawmills, textile mills, and even mines!

The most important reason to maintain mills was for safety. If the grindstones touched, they could cause a fire and even an explosion. Therefore, it was very important for a miller to always be aware of how the parts were working together in order to not create sparks, especially the millstones.

#### Modern Water Turbines 

* Today, water turbines are used to produce **hydroelectric** power instead of watermills. A key difference between **turbines** and water wheels is that **turbines** use water that swirls through blades that are curved or angled rather than flowing in a straight line. Romans were the first to use water **turbines**, but this invention did not become widely used until the Industrial Revolution. Several inventors tested and designed different **iterations** of the water **turbine**, and one of the most notable was James Bicheno Francis, whose new innovations led to the modern-day Francis Turbine. This type of **turbine** outputs roughly 60% of the world’s **hydroelectric** power. Francis’ main innovation was to create a turbine that used radial flow and minimized inefficiency or lost power. Radial flow meant that the water flowed horizontally to an inner wheel made of curved blades which spun, thus creating the “swirl.”
* In order for a **turbine** to generate a substantial amount of power, a **hydroelectric** dam is constructed. Rivers with a large drop in height are a prime location for a dam. Water stores more potential energy and thus can create more electrical energy if there is a larger difference between the elevation of the **reservoir** water behind the dam compared to the flowing river further down on the opposite side of the dam. Besides this height difference, the amount of available water also affects how much energy can be produced. For water to pass through, it must first enter near the bottom of the dam at the **intake**. Engineers are in charge of determining and controlling how much water enters the **intake**. As the water enters, it falls through the penstock with the help of gravity. As the water moves down the penstock, it reaches a **turbine** propeller. The **turbine** propeller is actually moved by moving water! This same **turbine** is also connected to a generator by its shaft. While the water continues onto the river stream below, coils inside the generator create electrical power. The generator connects to a transformer and long-distance power lines, or power transmission cables, next carry this electricity to our homes and communities.

#### Hydroelectric Power for Renewable and Clean Energy

* For a long time, many people have focused on the benefits of using **hydroelectric** power. **Hydroelectric** power relies upon moving water and does not lessen the amount of available water and is **renewable**, in the process of creating clean energy. Rainwater is also stockpiled in **reservoirs** for **hydroelectric** power plants, making more water accessible for our watering systems, farming needs, and human consumption. This recurring rainfall can be used to generate additional fuel as well or added to the electrical system if there is a sudden blackout or shortage and therefore a need for quickly-supplied additional energy. In addition, fuel is not burned and up until recently, it was supposed that greenhouse gases are produced with **hydroelectric** power, making it an energy solution that can help with addressing global climate change. 
* Besides confronting climate change, **hydroelectric** power is a lasting solution of affordable and clean energy. In fact, **hydroelectric** facilities typically last for 50-100 years, are low-cost to run and maintain, and are fairly straightforward to upgrade to the newest and latest technological advances. Hydroelectric power is dependable and understood, has been utilized for a long time and demonstrated to work, and ultimately can bring new development in the form of businesses, roadways, and energy that enrich and expand the economies of towns and cities where people live. Finally, **hydroelectric** power is better for the air, both for people and the environment, than fossil fuels. Unlike fossil fuels, hydropower does not pollute the air and contribute to the formation of microparticle toxins, smog, or acid rain in the air. Such pollutants lead to human sickness and death while also damaging our plants, animals, and their respective ecosystems. However, the encouraging news is that investment in hydropower is estimated to save over billions in healthcare and economic costs that could result from air pollution.

One of the main arguments for creating more electrical power through hydropower is it's renewability. Hydropower plants can use the same water over and over again to produce electrical energy and roughly the same amount of water is always on earth. In addition, it does not create smog or polluted air, thus it is also more beneficial for human health than burning fossil fuels.

#### Hydropower Controversy: Human Difficulties and Environmental Problems

* **Hydroelectric** power is not without significant controversies, especially concerning the environmental impact of creating **reservoirs**. These notable disadvantages and challenges affect humans, wildlife, and the environment. First of all, the clearing and submergence of land needed to create **hydroelectric** power plants can disrupt local ecosystems, causing loss of habitat and migratory patterns for land and aquatic wildlife. Hydropower plants can alter a river’s flow, water quality, or temperature, which may also affect local animal and plant life.
* Some especially controversial dam projects were the proposed construction of dams on the Little Colorado River in the Grand Canyon sites and surrounding land are important areas for **indigenous** people groups like the Navajo and Hopi people of North America. The Navajo, Hopi people, and other groups are currently working to oppose huge corporations in order to try to protect land and river areas that have been sacred for thousands of years. 
* Hydropower also contributes methane gas into the atmosphere. The vegetation that is flooded when a dam is constructed **decomposes** underwater and releases methane gas into the atmosphere. Some hydropower plants actually release more methane gas into the atmosphere than fossil-fuel burning plants, and methane is one of the leading causes of climate change.
* Another reason is making a **hydroelectric** plant is a significant investment cost and the build projects can take years to complete. Dams, **reservoirs**, and hydro facilities hold back a tremendous amount of water. If these water systems fail, the resulting floods can lead to a high loss of human lives, homes, and neighboring infrastructure. Factories, waste sites, and mines can even be **submerged**, causing significant pollution to local river systems.
* Last of all, hydropower is dependent on river flow and **precipitation**. Changing amounts of **precipitation** and resulting water supply over different seasons can impact the energy output of a hydropower plant. One solution to high amounts of rainfall and potential flooding is the use of a **spillway**. A **spillway** enables excess water to flow into another part of the river below, using a chute, step-down, siphon, or bell-mouth design, without overloading and harming the dam and the community below. **Spillways** remain dry most of the time.

Imagine

#### Facilitation and Collaboration Work

You can have students work on the instructions together in pairs of 2 going up to a group of 3.

Build water wheel paddles

Assemble the water wheel

Create an axle for the wheel

Balance wheels in hands and test under running water

Create

#### Facilitation and Collaboration Work

Students can work together on the instructions and take turns testing the pouring water on the spinning wheel of the grinding mill to align while another student adjusts the mill inside the container if it's moving around in between water pouring. Take care in letting students back away when water is released to avoid getting wet!

Build a stand for the water wheel

Close top of water wheel stand for axle

Fit water wheel and axle into the stand

Balance and test water wheel and stand under running water

Build the base of the mill

Build a beam for the grindstone

Make a moving joint

Switch corner of grindstone with joint

Attach the water wheel to the grindstone

Add an arm for the water wheel

Test the mill invention by pouring water to see how it spins

Build

#### Facilitation and Collaborative Work

For this section of the lesson, the following questions below can be discussed all together as a class or within each group. You can use the **Student Journal** asset as a helpful resource to capture ideas and process on the computer or printed ahead of time and distributed.

Reflect

Challenges

References and Extra Resources

STEAM Classroom

UK - England

Year 3

Year 4

Year 5

Year 6

UK - Scotland

Ensure access to affordable, reliable, sustainable and modern energy for all.

SDGs

Goal 7

Build resilient infrastructure, promote inclusive and sustainable industrialization and foster innovation.

Goal 9

Use research and develop design criteria to inform the design of innovative, functional, appealing products that are fit for purpose, aimed at particular individuals or groups.

National Curriculum

KS2-1

Generate, develop, model and communicate their ideas through discussion, annotated sketches, cross-sectional and exploded diagrams, prototypes, pattern pieces and computer-aided design.

KS2-2

Investigate and analyse a range of existing products.

Evaluate their ideas and products against their own design criteria and consider the views of others to improve their work.

Understand how key events and individuals in design and technology have helped shape the world.

KS2-3

Apply their understanding of how to strengthen, stiffen and reinforce more complex structures.

Understand and use mechanical systems in their products [for example, gears, pulleys, cams, levers and linkages].

Understand and use electrical systems in their products [for example, series circuits incorporating switches, bulbs, buzzers and motors].

Apply their understanding of computing to program, monitor and control their products.

KS2-4

I can describe the major characteristic features of Scotland’s landscape and explain how these were formed.

Curriculum for Excellence

SOC 2-07a

I can discuss the environmental impact of human activity and suggest ways in which we can live in a more environmentally responsible way.

SOC 2-08a

I can consider the advantages and disadvantages of a proposed land use development and discuss the impact this may have on the community.

SOC 2-08b

By considering examples where energy is conserved, I can identify the energy source, how it is transferred and ways of reducing wasted energy.

SCN 2-04a

I can investigate the use and development of renewable and sustainable energy to gain an awareness of their growing importance in Scotland or beyond.

TCH 2-02b

I can analyse how lifestyles can impact on the environment and Earth’s resources and can make suggestions about how to live in a more sustainable way.

TCH 2-06a

I can make suggestions as to how individuals and organisations may use technologies to support sustainability and reduce the impact on our environment.

TCH 2-07a

I can extend and enhance my design skills to solve problems and can construct models.

TCH 2-09a

I can recognise basic properties and uses for a variety of materials and can discuss which ones are most suitable for a given task.

TCH 2-10a

I can extend my knowledge and understanding of engineering disciplines to create solution.

🇬🇧 Hydropower Inventions

Overview and Objectives

Lesson Structure

Structure