Tag: Energy

ASHRAE Standard 90.1

ASHRAE Standard 90.1

12/10/17

“What is the basis for building energy efficiency in the U.S and much of the world?”

With the onset of global warming, energy efficiency has become a great necessity. As such, buildings in the U.S must now follow a certain standard so that after construction they will meet the sustainability requirements dictated by ASHRAE Standard 90.1. ASHRAE Standard 90.1 is a compilation of all of the codes for building energy efficiency (with the exception of low rise residential units) and is updated every three years to ensure that the next set of codes will be 15 percent more efficient than the previous.

The Rankine Cycle

The Rankine Cycle

12/07/17

“How can we predict the performance of steam turbines?”

Steam turbines are some of the most used energy systems in the world. As such, it would be very practical to analyze how they consume energy. However, because of intricacies in internal operations, the Carnot Cycle will not work. So how can we use our engineering mindset to model steam turbines? Well, let’s use our engineering mindset to find out. To begin, let’s pump our working fluid from a lower pressure to a higher one in Process 1-2. Then, this high-pressure liquid will enter a boiler to be heated by an external source at a constant pressure until it becomes a dry, saturated vapour in Process 2-3. Afterwards, let’s put this through a turbine, generating power. This Process 3-4 will decreases the temperature and pressure of the vapour, and some condensation may occur. Finally, let’s end this by putting the water through a condenser and condensing it to a liquid at constant pressure until it becomes a saturated liquid in Process 4-1. This cycle is known as a Rankine Cycle and has become the foundation for all steam turbine energy systems.

Nonintrusive Load Monitoring

Nonintrusive Load Monitoring

11/26/17

“How can we determine the appliances in a building just from its energy consumption?”

As Engineers, it would be very useful to analyze the types of appliances within a building. However, doing so requires a heavy upfront investment in a large multitude of sensors.

Or does it?

After many years of research, Engineers and Scientists have developed a method known as Nonintrusive Load Monitoring, which takes in data from a building’s energy uses, parses out all of the patterns, and recognizes which appliances are in the unit. Although novel and affordable, one serious drawback with this technology is privacy concerns, since large organizations will be able to snoop in on the appliances that an individual possesses.

PV monitoring

PV monitoring

10/22/17

“How can we monitor the efficiency of our solar power systems?”
Solar panels are pieces of very active technology. And as such, they are prone to fluctuations in reliability and efficiency. So how could we monitor such changes? Well, what if we were to use software that detected such effects? This is the fundamental idea behind PV monitoring and is used in industries all over the world.

How Renewable Energy is Helping Grid Stability

How Renewable Energy is Helping Grid Stability

10/16/17

“How can renewable energy increase grid stability?”

Numerous critics of renewable energy believe that by increasing its usage will make the grid more unstable due to the fluctuating nature of the sun and wind. However, a leaked six-page document from the U.S Department of Energy has found that such claims are unfounded and that the increased use of energy efficiency, battery storage, and demand response was actually making the grid more reliable! Just goes to show that with a little bit of science even the most intuitive of perspectives can be proven untrue.

Why Lithium-ion Batteries are Better for Renewable Energy Integration

Why Lithium-ion Batteries are Better for Renewable Energy Integration

10/11/17

“What is one possibility to solve renewable energy storage?”

Subject Solar Energy / Storage Innovations

Date: October 11, 2017

Purpose

I am writing to you to inform you about recent difficulties in solar energy integration. As it stands, solar energy is generated in an active form, meaning that once created it must be used immediately. To solve this, we can deploy Lithium-ion batteries to act as reservoirs.

Summary

Lithium-Ion Batteries have properties that make them a strong option for renewable energy integration. Lithium-ion batteries are composed of lithium and carbon, giving them special characteristics. However, these same properties also give Lithium-Ion Batteries special problems, such as being prone to spontaneous explosions. (Brain, 2006)

Background

One of the major bottlenecks to renewable energy integration is a lack of viable storage mechanisms. One of the most viable solutions, battery systems, has numerous drawbacks. They can take up large amounts of space, and provide a low energy to space ratio. Consequentially, the current battery technology paradigm needs to be overhauled.

Discussion

Introduction

Lithium-Ion Battery Technologies are a new battery technology. Because of their unique properties, they hold much potential for Renewable Energy Storage. However, this same composition that makes it special also makes it potent for mishap.

Advantages

Lithium-ion Batteries include numerous advantages. Their much more energy dense, meaning that a small volume can hold a lot of charge, bypassing the previous space issue. They also tend to keep this charge, losing only 5%/month compared to the average 20%/month, allowing renewable energy to be stored for a longer time. They also can also be charged before they run out of power and can handle hundreds of charge/discharge cycles, making them quite viable for being used as battery storage with the dynamic character of renewable energy. (Brain, 2006)

Drawbacks

These batteries also come with numerous drawbacks. They start degrading once manufactured, decay faster in the presence of high temperatures, are ruined upon complete discharge, require an onboard control system, and most importantly, may burst into flame spontaneously if it overheats. (Brain, 2006)

How we can overcome this

Keep these batteries in low-temperature facilities. This will keep their charge more stable, have it degrade slower, and most importantly prevent spontaneous explosions.

Conclusion

Even with their flaws, Lithium-ion technology holds much potential for use in renewable energy integration. Their high energy density combined with their ability to handle dynamics charging and discharging gives them an unparalleled capacity to work with renewable energy. If we can store them in colder locations, then we can also greatly reduce their drawbacks.

References

Brain, Marshall. “How Lithium-Ion Batteries Work.” How Lithium-Ion Batteries Work | HowStuffWorks, HowStuffWorks, 14 Nov. 2006, electronics.howstuffworks.com/everyday-tech/lithium-ion-battery.htm.

Grid Resilience

Grid Resilience

10/10/17

“How can we measure how resilient the grid is?”

Grid reliability is a great way to measure the stability of the grid. But unfortunately, it does not give us the complete picture. When a grid systems experience are taken down, they need time to recover. The less time it takes, then the more resilient a grid will be. Taken the two systems in the picture for example. When the bottom one experiences a disruption, not only will it need a long time to recover but it does not reach close to its full potential again. In contrast, the top one only experiences a brief hiccup and quickly flows back to normal. This measure is called Grid Resilience and is an important part of the analysis of electrical systems.

Electric power systems

Electric power systems

08/19/17

“What is the framework that powers our infrastructure?”

A great proportion of our modern infrastructure is contingent upon electricity for operation. However, what exactly is the fundamental framework behind all of it? Well, let’s take a close look. We know that we can simplify the course of electricity into 3 components: generation of power (through means such as solar panels and wind turbines), transmission of power (with means like HVDC), and distribution of power(using machines like transformers and grid tied inverters). If any framework has these three components, then it can be classified as an electric power system. The most famous example of an electric power system is the grid, which permeates nearly every aspect of our daily lives.

Demand response

Demand response

08/02/17

“How can we prevent a grid overload using a simple technique?”

We have a problem. We would like the demand usage for the electric grid to be as equalized as possible, such that the electricity drawn in at one time would look the same as the electricity drawn in at another. But this is almost never the case. Instead, the demand for the grid varies greatly throughout the day. And sometimes these demand peaks are so high that they destabilize the grid! So how can we use our engineering mindset to solve this problem? Well, what if we were to just shift electricity usage from times of peak load to times of less intensive load? This is the fundamental idea behind demand response and can be accomplished with economic incentives and through smart electricity control.