# Basic question about energy conservation

• mcolom
In summary, a new revolutionary artificial muscle has been developed that utilizes the principle of heat-induced contraction to generate a force. However, the heat only triggers the release of stored energy, not create it. Calculations using the mechanical and thermal properties of iron show that there is no extra energy being created in this system. Additionally, the watt is a unit of power, not energy.
mcolom
Hello

I just read this http://io9.com/scientists-just-created-some-of-the-most-powerful-muscl-1526957560 where they explain a new type of revolutionary artificial muscle.

The principle of operation is very simple: when a material gets hotter, it contracts and generates a force. I already knew materials can expand or contract when their temperature vary, but it looks like i haven't thought about it deeply enough.

If I have a thin bar of a metal tied to the roof, and 1 ton of iron tied to the bar. Then, I spend 1 watt of energy to cool the bar, and it contracts by 1 cm. This contraction lifts the ton of iron, increasing its potential energy by much more than 1 watt. Loos like I'm creating energy, which of course its not possible, but that's my question: where is that energy coming from?

Best regards

Hi mcolom, welcome to PF!

There is no extra energy in this system. These materials are loaded under tension in order to form the artificial muscle. That loading under tension requires a substantial amount of energy. The heat doesn't provide much, if any, of the energy. It merely triggers the release of the energy that is already stored.

mcolom said:
Hello

I just read this http://io9.com/scientists-just-created-some-of-the-most-powerful-muscl-1526957560 where they explain a new type of revolutionary artificial muscle.

The principle of operation is very simple: when a material gets hotter, it contracts and generates a force. I already knew materials can expand or contract when their temperature vary, but it looks like i haven't thought about it deeply enough.

If I have a thin bar of a metal tied to the roof, and 1 ton of iron tied to the bar. Then, I spend 1 watt of energy to cool the bar, and it contracts by 1 cm. This contraction lifts the ton of iron, increasing its potential energy by much more than 1 watt. Loos like I'm creating energy, which of course its not possible, but that's my question: where is that energy coming from?

Best regards
Did you actually run any calculations using the real mechanical and thermal properties of iron to evaluate this? My guess is that you are just pulling numbers out of the air. When you do run the calculations, you will find that energy is not being created. One other issue: the watt is a unit of power, not energy.

## 1. What is energy conservation?

Energy conservation is the practice of using energy efficiently and reducing energy consumption to save resources and decrease negative impacts on the environment.

## 2. Why is energy conservation important?

Energy conservation is important because it helps to reduce our reliance on non-renewable energy sources, which are finite and contribute to environmental degradation. It also helps to save money on energy bills and reduce carbon emissions, thus contributing to mitigating climate change.

## 3. How can I conserve energy at home?

There are several simple ways to conserve energy at home, such as turning off lights and electronics when not in use, using energy-efficient light bulbs and appliances, properly insulating your home, and using natural lighting and ventilation when possible. You can also consider using renewable energy sources, such as solar panels, to power your home.

## 4. What are some examples of energy conservation in everyday life?

Some examples of energy conservation in everyday life include taking public transportation or carpooling instead of driving alone, using a reusable water bottle instead of buying plastic ones, using natural light and air instead of artificial sources, and unplugging electronics when not in use.

## 5. How can businesses contribute to energy conservation?

Businesses can contribute to energy conservation by implementing energy-efficient practices, such as using energy-efficient lighting and equipment, conducting energy audits to identify areas for improvement, and encouraging employees to conserve energy. They can also invest in renewable energy sources and support initiatives that promote energy conservation.

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