“What happens when renewable energy becomes cheaper than it’s more corrosive counterparts?” One of the major slanders against renewable energy is that it is too expensive to compete with traditional sources such as coal and petroleum. However thanks to the efforts of generations of scientists and engineers, the upfront cost for cleaner systems has dropped exponentially in the past few years, so much so that countries and states such as California and Germany have reached something called grid parity, or when renewable prices actually become cheaper than their corrosive counterparts with no subsidies! In fact, solar energy prices are falling so fast against rising electric utilities that according to a recent report by Deutsche Bank, 80% of the world market will have achieved grid parity by 2017!
“How can we achieve greater efficiency of solar arrays using water?”
Solar panel arrays are some of the most benevolent technologies in existence. However, they can often require large parcels of land, which could be expensive and take away from the possibility of being used for other activities. So how can we use our engineering mindset to circumvent this issue? Well, if our main quandary is that solar panels take up a large amount of land, why not take them off land? Specifically, what if we were to create solar panels designed to float on water? This is the operating principle behind floating photovoltaics (also known as “floatovoltaics”), which use a specialized form of solar panels placed in water reservoirs to generate clean electricity for the local area. Floating solar arrays are more efficient than traditional models and can be hidden from the public view, but designers of such systems must take into consideration the effects of increased wind speeds over water and the local habitat. Companies around the world are already suiting to take up the challenge of implementing these systems, with Kyocera of Japan, Sonomoa clean power of California, and Infratech industries of Australia investing money to build these models.
“How can renewable energy sources give back to the grid?”
Grid connected renewable energy systems can easily receive energy from local power generation units when there is a deficit. However, would it also be possible to send over energy to the grid when there is a surplus?Well, let’s think about it. If electricity can be received from a power generation station (such as a coal plant) one way, then wouldn’t it be logical to send electricity generated (such as from a solar panel) the other way? Furthermore, since individuals are billed for every time they receive electricity from the grid, couldn’t individuals bill the electric company for this activity? This is the fundamental idea behind net metering, which uses a bi-directional meter to measure the net energy received/given off by a housing unit to determine the compensation. Net metering has already spread it’s away across the United States, and hopefully one day the entire world!
“Why are wind turbines placed at higher altitudes?”
Wind turbines are a very common sight nowadays. However, if you look closely, you can notice a recurring pattern: such edifices seem to be disproportionately placed at higher altitudes. Why is this so? Well, we simply have to analyze the physics and engineering surrounding the decision. When the planet’s wind collides with solid objects, turbulence will generated, disrupting wind flow and inducing a lower speed. The closer the wind is to the ground, the closer it will be to solid objects, causing more turbulence, and since the amount of energy that a wind turbine produces is contingent to the surrounding wind velocity, it would be only logical to place them at higher altitudes.
“Why is it that wind turbines always seem to have three blades?” Wind turbines can be seen everywhere nowadays, from the coasts of Brazil to the mountains of Scotland. Throughout these installations, they all seem to have one peculiar feature in common: only three blades are attached to the turbine. Why is it like this? Well, let’s use our engineering mindsets to figure this out. The more blades that a wind turbine has, the more torque, generating more electricity. However, each blade will come with its own particular weight and cost, so simply adding more would prove ineffective. If one were to create a performance vs cost analysis, they would find that the three blade design would come out as the most efficient! This little example is a great showcase for how engineering is not utterly based off the laws of physics but the nature of economics as well.
The Netherlands’ electric is now completely powered by renewable energy
01/13/17
“How is it that the Netherlands’ electric train system is now completely powered by renewable energy?”
A most riveting milestone in global renewable energy adoption has just been reached. The Dutch national railway company NS has just announced that the entirety of their electric train fleet is running on renewable energy! This means that transportation systems that carry 600,000 passengers every day have and consumes 1.2 billion Kwh each year has just had their carbon footprint sabotaged! However, work is not done, as the company also plans to decrease energy used per passenger by 35% by 2020
“How can we ensure that a battery does not get depleted or overcharged while we are using it?”
Much of our current technological operating infrastructure rests upon battery technologies. These simple devices allow us to store energy in a portable format for later use, such as in electric vehicles and micro-grid systems. However, because they are so vital for many systems, if they become depleted or overcharged, then all operation could be thrown into catastrophe. So how can we modify such systems to ensure that the state of charge for batteries are always at a stable level? Well, let’s use our engineering mindset to solve this issue. For this sort of problem, it looks like some sort of monitoring would be needed. So what if we made a device that could sense if a battery was becoming overcharged or over discharged it would shut down current? This is the operating principle behind a technology known as charge controllers, which have become an essential part for numerous renewable energy systems.
“Can we combine both the series and parallel hybrid car drivetrains?”
Both series and parallel hybrid car drivetrains offer their distinct advantages and disadvantages. The exclusionary principle of the series drivetrain allow for greater efficiency at lower speeds, while the combined efforts model of the parallel drivetrain allow for a smaller battery. However, would it be possible to combine both types in an attempt to have our cake and eat it too? Well, it turns out such a wild idea is indeed possible through the use of a series/parallel hybrid car drivetrain. These drivetrains are set up so that the electric motor and internal combustion engine can operate independently of the condition of the other. This allows for much greater efficiency than either component acting completely discrete or in union. However, these systems will come at a higher cost, making it prohibitive for many individuals to purchases such systems. Perhaps one day, the cost of the systems will plummet to the point that they will threaten to encapsulate the entire market.
“How can we create a more hybrid car drivetrain more efficient for busy traffic?”
Parallel hybrid car drivetrains are wonderful contraptions, but they come with one downside. Much of the efficiency benefits gained from electric vehicle technology are lost during busy “stop and go” traffic, where the internal combustion engine will impinge upon the other components. So how could we get around this problem? Well, let’s use our engineering mindsets to solve this problem. We know that the inefficiencies only come along when the ICE is in use. So what if we were to create a system in which we could control the amount of power that the motor receives from the battery and ICE? Well, it turns out that this concept has already been put into practice as a series hybrid car drivetrain. The operating principle behind these mechanisms is that an onboard computer will measure the speed and acceleration of the vehicle, and use predetermined algorithms to control the power intake of the ICE vs the battery. Due to the larger power requirements, series hybrid car drivetrain systems require a larger battery and motor.
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