This journey traces our electrical power to its source – in three parts.
Parts one and two follow the journey from our home in northern New Jersey, to just below the New York State line where this image was taken. A connection with this 138,000 volt transmission line and the moon will be noted at the end of this post.From our neighborhood ….along the local distribution grid …and through two sub-stations, we follow about seven miles to where it comes in from New York State, from the north. A few miles further, these towers meet up with others at a significantly larger sub-station which fans transmission lines out in several directions. A primary “incoming” feed, is seen below.Probabaly in the 345,000 to 500,000 volt range, the cables on these structures carry serious loads, coming into the sub-station shown in the previous photo,Here is a close-up of two cables bonded together, presumedly at the same alternating current phase, …for those of you who worry about such things. Each is about a closed fist in diameter and insulated only by the air. The larger spiral wires simply hold the cables to the brace.Heading south (right in this image,) over hills and valleys from Tomkins Cove, these imposing mono poles transfer the power lines from the western end of the trans-Hudson span (out of sight to the left.) The frame transmission tower in the background is not directly related. Standing some 475 feet (148 m) high and separated by nearly a mile (1.6 km,) these towers carry 500,000 volts or more across the Hudson River….The top hand railing seen in both the photo above and those below indicate scale: about 4 feet (1.2 m) high. Note the relative size of the insulators!
About a mile (1.6 km) left of the eastern tower are the two reactor domes of the Indian Point Nuclear Generating Plant, in Buchanan, New York.The magnetic-induction generators within, produce a three phase AC potential of several thousand volts, which is immediatly STEPPED-UP through transformers to the half million to 750,000 volt conductors exiting the plant. The lines coming out of the building just right of center, and to the transmission tower behind, mark the start of the transmission lines traced by this series. Others feed Westchester County and parts of NYC… with significant presence also on the North-East U.S. regional grid.Technically: Inside Indian Point. An alternating current is produced in three phases, induced in coils of wire moving in strong magnetic fields within these generators. Relative movement must occur between the magnet assemblies and the coiled wires. The resulting electromotive force is measured in volts, and leaves the generator first at a few thousand, then stepped up, via powerful transformers, to 500,000 to 750,000 volts for transmission… and for our use, sent across the Hudson River!The relative movement mentioned above is provided by a shaft directly connected to a steam turbine that spins the magnets, (or visa versa, the coils,) within the generator. Technical Morass Follows: The steam is is produced in a kettle in which Hudson River water is heated via a water exchanger. That water, which is in a closed system, and highly pressurized, surrounds the reactor vessel where a form of slightly enriched uranium dioxide is fissioned by neutrons (usually under initial coaxing,) releasing heat energy and more neutrons to sustain a controled chain reaction. Spltting atoms! Uranium “pellets” are bundled as fuel-rod assemblies within the reactors core. Basic Summary: Simply, heat energy from unranium fission heats river water to make steam that turns the turbines that spin the coils (or magnets) in the generator, producing the dance of electrons –>electricity!The rods that fuel the reaction in the reactor’s core is comprised of compressed uranium dioxide pellets, which in turn is processed from uranium – a naturally occuring element in the earth’s crust. Above is a rock sample containing uranium. It is likely this is also part of the moon’s geologic make-up. (Remember the moon?)FINALLY, (Thank Goodness,) naturally occuring uranium and the earth itself, with its myraid forms of latent energy, originated as a spin off from our sun 4.5 billion years ago. For now, and for the purpose of this project, the source of my warmed toast, is…the Sun. It’s all amazing, and amazing how we naturally take the science, (physics, chemistry etc.,) and resourceful human ingenuity …for granted!
Disclaimer: Not being an electrical engineer or public utility employee, some values may be slightly different than stated, but should give a general idea of the actual grid and electrical generation. Any “system” or statistical corrections will be most appreciated.
With the exception of the I.P.Generator, the diagram and the uranium ore above, all photos in this series were taken by myself. General information, and those three photos are greatly apprieciatiated and obtained from various sources, including the internet. Additional information about this is available if requested.
As usual, thanks for viewing, and comments are always welcome. M:-)
This journey traces our electrical power to its source – in three parts.
Our house is to the left. That single 7,200 volt wire and the bare ground wire (the latter dificult to see,) come into the picture from the left and join with one of three wires making a turn to the right. The power that is delivered to our house can come from either direction, as multiple loops of triple 7,200 volt lines (and a separate ground wire) form a redundant grid which can be switched in advantageous ways to better insure connectivity – as events occur. Three wires, and a ground. This is the same configuration comprising transmission from the generator to every local neighborhood. Technically: Long distance transmission is much more efficient with three alternating current phases, each generated 120 degrees apart, and in the case of most of the USA, at 60 cycles per second. It hurts my head to visualize the principles involved, but the effect justifies the need for three conductors, or wires. Overhead: As seen in the first image above, only one of these wires is neccesary to supply each house. The bundle above, however, is typical to efficiently bring the necessary voltage to NEAR our homes. About a quarter mile away from home is a junction of two routes, again, with three 7,200 volt feeds, and one common ground. The ground is connected as a bare wire down virtually every pole to the soil beneath, or as in this case, serving the dual purpose of a guy wire. (Lower down the pole in this image, 110 volt wires from nearby transformers, feed houses and the streetlight.)On either side of the junction shown in the previous image, these arrays serve as a computerized reclosure system. The second crossbar down holds six conventional manual circuit breakers. Then, each wire enters the components in the rack, continuing down on the far side of the pole to a control panel at street level. It detects failures, assess the impact and instantly re-directs or cuts off power; and if deemed only a momentary stoppage, re-connects in seconds. A telemetry antenna on the lower side independently transmits info to the utility company via battery back-up. Click to enlarge and see details of this remarkable grid component.Reclosure Control Panel at Street Level
Sandy and I often walk under two of these reclosure arrays in an area two blocks away from home known locally as “Doggie Triangle!” Two miles away, the three conductors emerge from a small sub-station, as seen below.
Here, are the three 7,200 volt lines coming out of the nearby sub-station after having been ‘stepped down’ from 69,000 volts.Coming into this same sub-station, we trace three (of six) 69,000 volt conductor wires (faintly seen dipping down from the hi tension mono tower,) with a fourth (ground wire) way on top. These are handled by the framework, right, and drop down in the foreground, entering the transformer area, out of sight below. The transformers step their voltage down to 7,200 each after which they exit the sub-station as shown in the previous photo.About 6 miles further north, the S. Mahwah sub-station covers several acres with many more transformers, capacitors, reclosures, bus bars and dead squirrels. Coming in from NY State are some serious power towers, possibly carrying 138,000 volts. This image is where that force of power is handled and stepped down to the 69,000 volt towers seen in the previous image, and also several 7,200 volt bundles exiting to local loops which redundently serve as backups spreading out into the region.At least 138,000 volts in 4 groups of three wires (left towers) come into the S. Mahwah sub-station (in the diatance) from New York State, behind me in this view.
The next Part follows the link another 25 miles or so to the massive Indian Point Nuclear Power Plant, the source, …where electricity is generated from the heat released from Uranium 235 fission.
Disclaimer: Not being an electrical engineer or public utility employee, some values and circumstances may be slightly different than stated, but should give a general idea of the actual grid. Any system or statistical corrections will be most appreciated.
As usual, thanks for viewing, and comments are always welcome. M:-)
Part One: Pondering while Eating Toast: Bread Crumbs to Utility Pole.
This journey traces our electrical power to its source – in three parts.
How does the ubiquitous energy that we take for granted come to our homes? Where does it start? How does it happen? What’s all that stuff up there on the “utility” poles? In my case a 35 mile (56 km) drive up to Tomkins Cove, NY, reveals these two enormous 475 foot (148 m) towers supporting 12 fist size cables across the Hudson River – freshly energized with something like 500,000 volts.
No Time? Just view the images, which will appear in higher resolution when clicked. The captions tell the story.
Walking Sandy Paws, the dog, most mornings, I find myself looking up at the utility poles with their strings of wires overhead, – everywhere – seemingly not much different than 120 years ago in the big cities. What’s up? So I grabbed my camera and did some investigating, starting with my morning toast.
When the toaster is turned on, a circuit is complete across the heating elements which literally become “red” hot, and my bread is toasted. Yum! Technically –> Current is now flowing from the narrower (hot) slot of the wall outlet above [which is connected to one of two 120 volt wires entering the house’s service panel] to the “neutral” (wide slot in the outlet,) where, after effectively drained of voltage by the toaster’s elements, it dissipates residual to the earth. Painfully –>If YOU grabbed the hot and neutral wire, YOU would be toast! Wall outlets (for example) are wired to circuit breakers in the service panel which, in turn are connected to either one of two 120 volt lines entering the house… and the ground wire. Seen here, those three wires enter via the yellow painted sheath above the panel, one of the 120 volt lines is seen (in brown fabric covering) inside the panel, coursing down and left above the white neutral (ground) wires. A similiar (black fabric covered) wire is to its right. (Click and enlarge for detail.) The bare ground wire from the yellow sheath is solidly attached to the panel itself, the neutral side of circuits, and in turn to the water pipes as an additional ground assurance. As long as either of the two feed wires and the ground wire are NOT connected, (from power plant to toaster) virtually no current flows.Painted yellow inside the house, here are the sheathed three wires, entering the foundation.Attached to the side of the house, two insulated 120 volt lines and one bare ground wire enter the sheath together, coming from the pole on our street.The three wires, twisted together, join (connect directly) with those of three other houses, and come from the pole’s transformer. Just to make it really confusing, all the wires are a mess up there on our pole but at least you can see a connector wire coming down from a single 7,200 volt line above into the top of the transformer. The windings in the can step the voltage down to two identical 120 volt lines, which along with the supporting ground cable, go to the house. See clearer image below.In this view of an almost identical single phase transformer, the two 120 volt feed wires and one ground wire clearly come out of the upper side of the can and twist at the bottom right towards the house. (Image from Wikipedia) (The device above the can is an overload circuit breaker on the feed wire.)
…So, right outside our home, a pole supports a 7,200 volt feed wire (it may be as high as 13,200 volts,) and transformer which steps voltage down to 120 volts and connects directly to our house.
Disclaimer: Not being an electrical engineer or public utility employee, some values and circumstances may be slightly different than stated, but should give a general idea of the actual grid. Any system or statistical corrections will be most appreciated.
As usual, thanks for visiting, and comments are always welcome. M 🙂
