Month: December 2017

Pyrheliometers

Pyrheliometers

Pyrheliometers

12/22/17

“How can we measure direct sunlight irradiance?”

 

One of the most important things for an area’s solar energy potential is the amount of direct solar irradiance. However, how can we measure this? Well, let’s use our engineering mindset to solve this. First, let’s make a portable apparatus. Then, let’s put a window in this device such that sunlight can be collected. Let’s then focus this slight onto a thermopile, and convert the heat generated into an electrical signal which can describe the power incident on the panel. This machine is known as a pyrheliometer and is vital for measuring solar energy.

Thermal Power Stations

Thermal Power Stations

Thermal Power Stations

12/21/17

“What type of facility can convert thermal energy to electrical?”

 

Energy can be generated in a wide multitude of methods. However, (and perhaps unfortunately) the most popular method is to heat an energy dense material to boil water into steam to drive a turbine. This facility known as a Thermal Power Station. Thermal Power Stations usually operate under a Rankine Cycle and can run on multiple types of input such as coal, petroleum, and municipal waste.

Cooling Towers

Cooling Towers

Cooling Towers

12/20/17

“How can we cool a large flow of water?”

 

Water is often used to cool buildings. However, during the process, it absorbs heat from its surroundings, thereby warming it up and making it less usable for future use. So how can we ensure that this water can be cooled down to usable levels? Well, let us use our engineering mindset to find out. We know that if water comes into contact with surrounding air, it will cool down a bit, and some may even evaporate. So what if we were to take our stream, move it through condensers, causing some to evaporate and the rest to cool down to a workable state? Well, this technology is known as cooling towers and is used in industrial processes all over the world.

Head Loss In Fluids

Head Loss In Fluids

Head Loss In Fluids

12/19/17

“How do fluids lose potential due to viscosity?”

 

Understanding of fluids has led to some of the most important breakthroughs in engineering. However, when analyzing these systems, it is very important to take into consideration that viscous forces will act upon the fluid in transit. So how can we take this into account? Well, what if we were to just take into account all of the losses from both frictional and inertial changes? This is known as the head loss in fluids and is one of the most important foundations of one’s study of fluid mechanics. Head loss can be visualized by the pressure drop in a manometer like the one shown in the picture.

Isobaric processes

Isobaric processes

Isobaric process

12/17/17

“What is a thermodynamic process in which pressure remains constant?”

 

One of the defining features of a thermodynamic process is that the state of the system will change with time. However, in some of these processes, not all of the properties of a state will change. An example is Isobaric Processes, in which the pressure of a system will stay constant throughout the process. The work done under an isobaric process can be very simple to compute, being proportional to the change of volume W = P(v2-v1).

California Title 24

California Title 24

California Title 24

12/17/17

“What is the official building energy efficiency standard for California?”

 

In the U.S, most building efficiency standards are regulated by ASHRAE 90. However, some states go a little bit further with their regulations. In California, a series of codes known as Title 24 is the law of the land. Title 24 contains all of the specifications that a construction firm must consider before going through with a project. These include a requirement for LED lights, motion sensors for buildings, a specified minimum reflectivity for roofs,  electrical service panels for disaggregated measurement, and many other variables. California Title 24 is updated every 3 years such that the next set of rules saves more energy than the last.

Energy Recovery Ventilation

Energy Recovery Ventilation

Energy Recovery Ventilation

12/15/17

“How can we use stagnant building air to do something productive?”

 

When air is trapped inside a building for too long, it can become unhealthy and stagnant. However, could we possibly use our engineering mindsets to do something productive with this? Well, we know that heat exchangers can be used to make use of any fluids. And oftentimes, incoming air into buildings is suboptimal. So what if we were to use a heat exchanger to cycle the external air with the old interior air to keep our building fresh? This system is known as  Energy Recovery Ventilation and holds much promise for the future of the HVAC industry.

Electric Sub-Panels

Electric Sub-Panels

Electric Sub-Panels

12/15/17

“How can we distribute electricity in a larger building?”

 

Electrical service panels are ubiquitous in integrating an edifice to the grid. However, sometimes a building unit can become too large for just one subpanel. However, what if instead we were to just hook up a smaller panel to the larger one? Think of it like attaching a multi-plug to an outlet. These Electric Sub-Panels can now be found in built environments all over the world.

Electrical Service Panels

Electrical Service Panels

Electrical Service Panels

12/14/17

“What connects a house to the grid?”

 

Electricity from the grid has made modern living much better, whether it be in the lights that allow us to stay up late into the night, the HVAC systems that keep our place cool, or the energy that powers our computers. However, what exactly connects these services to our built environment? Well, let’s use our engineering mindset to think of it.

 

First, we will need a central location to keep all of the connecting circuits. This will allow us to centrally deliver power throughout a unit. We must also keep in mind that a circuit overload may occur, in which case circuit breakers will be attached. Now let’s place all of these in a central frame, making a device called an Electrical Service Panel. Electric Service Panels are one of the foundations of modern home energy systems and can be found in nearly every grid-connected building.