+- +-

+-User

Welcome, Guest.
Please login or register.
 
 
 
Forgot your password?

+-Stats ezBlock

Members
Total Members: 38
Latest: Dave Pugner
New This Month: 0
New This Week: 0
New Today: 0
Stats
Total Posts: 6824
Total Topics: 207
Most Online Today: 4
Most Online Ever: 48
(June 03, 2014, 03:09:30 am)
Users Online
Members: 0
Guests: 0
Total: 0

Author Topic: Undersea Turbines  (Read 386 times)

0 Members and 0 Guests are viewing this topic.

AGelbert

  • Administrator
  • Hero Member
  • *****
  • Posts: 6654
  • Location: Colchester, Vermont
    • View Profile
    • Agelbert Truth AND Consequences
Undersea Turbines
« on: November 21, 2013, 03:09:26 pm »
TidalStream Seeks Partner to Test Ocean Turbines in Deep Waters




Louise Downing, Bloomberg
November 21, 2013

LONDON -- TidalStream Ltd., a maker of platforms for tidal-power turbines, is in talks with energy companies and utilities to test its technology in deeper waters.

TidalStream is seeking to form a partnership next year, John Armstrong, a director at the London-based company, said in an interview. It’s talking to turbine makers, marine companies, shipyards and utilities based in Europe, Asia and Canada.

“We’re open to any deal structure,” Armstrong said by telephone. “Developing deepwater sites will be expensive, so we want to engage with companies that have the resources needed to provide that capital and to provide know-how as well.”

The tidal-energy industry is still in its infancy, with developers working to market their turbines and bring commercial-scale projects into operation for the first time. Tidal energy costs about $440 a megawatt-hour, more five times the cost of coal-fired power, according to Bloomberg estimates.

TidalStream’s platforms can accommodate groups of turbines at varying water depths. The technology has the potential to cut the cost of installing turbines by half, according to Armstrong.

“Turbine makers seem to recognize that this is one way to reduce costs,” he said. “Most of them have been busy solving the problem of putting turbines in the water, so they are receptive to the idea of lowering costs and solving the access and maintenance and installation problems in one go.”

A future partnership may bring TidalStream together with more than one company, Armstrong said.
Copyright 2013 Bloomberg

http://www.renewableenergyworld.com/rea/news/article/2013/11/tidalstream-seeks-partner-to-test-ocean-turbines-in-deep-waters?cmpid=rss

My comment:
A. G. Gelbert
November 21, 2013

When they finally get around to it, the obvious fact that massive and unlimited energy is available from the gulf stream less than 50 miles from high energy demand population centers on the Eastern Seaboard of the USA, this source of energy will become the major input there.



The USA has been building submarines for over 50 years. The hydrodynamics of undersea large propellers is well understood and engineered. Pushing a nuclear submarine along is far more challenging than anchoring a structure on the bottom that does not have to deal with varying water pressures or large temperature changes. Also, the lack of oxygen at depth inhibits metal corrosion and enhances multi-decade MTBF for undersea turbine metals.



It's time this was embraced worldwide. Undersea currents with titanic energy potential exist all over the oceans 24/7 and will be available as long as the planet earth rotates on its axis.



We need fossil and nuclear fuels like a HOLE IN THE HEAD!

http://renewablerevolution.createaforum.com/index.php
Leges         Sine    Moribus     Vanae   
Faith,
if it has not works, is dead, being alone.

AGelbert

  • Administrator
  • Hero Member
  • *****
  • Posts: 6654
  • Location: Colchester, Vermont
    • View Profile
    • Agelbert Truth AND Consequences
Re: Undersea Turbines
« Reply #1 on: December 27, 2013, 06:23:35 pm »
Agelbert NOTE: I am posting this here because the very same cables that are used fro offshore wind can ALSO be shared with undersea turbines for multiples of the power wind alone can provide. Plus, undersea current is baseload quality 24/7! 


Subsea Cables Bring Offshore Wind Power to the People

Cables are increasingly recognized as a crucial aspect of wind farm construction and operation. Here, we offer a glimpse of a Norwegian subsea cable manufacturing facility and review the challenges of this evolving market.

Tildy Bayar, Contributing Editor
December 19, 2013 

LONDON -- It might be surprising to learn that Norway’s tallest building is Nexans’ 120-metre extrusion tower at the company’s submarine high-voltage direct current (HVDC) cable factory in Halden. Nexans makes subsea cables that connect offshore wind farms to the grid, transports them around the world and installs them underwater so that the cables can bring clean power from offshore wind farms to onshore substations and from there to our homes.

Several different types of cable are used in offshore wind projects. Low (up to 1 kV) and medium-voltage loop cables transmit the electricity produced in the turbine’s generator to the transformer, usually located at the tower’s base. Then array cables connect the turbines on a wind farm to each other and export cables carry their power to the grid. Finally, underground and overhead line (OHL) cables that make it all work on land.


Offshore wind export and inter array cable types. Credit: Nexans.

On a recent tour of the factory, sponsored by Nexans, guides explained that the high tower at the Nexans factory houses the vertical extrusion machinery that begins the cable-making process. From “clean rooms” at the top of the tower, superclean polyethylene and cross-linkable, super-smooth “semicon” are fed through a closed system of huge tubes back down to an extruder at ground level, where the conductive material and insulation are spit out simultaneously from multiple extruders that feed into a single head. The tower can produce 15 km of cable in one week before the workers have to stop the process to change the enormous receiving baskets.

The height of the tower is important because all of the heat must be removed from the materials before they enter the tube. Curing and cooling takes place in a dry atmosphere of pressurized nitrogen in the building before the materials are fed from the tower to various stations in other buildings through “cable ways” which are little wheeled tracks running across and between buildings.
Using copper, aluminum, lead and wire, the materials are formed into cable lengths weighing up to 400-500 kg. At the end of the process the lengths are combined using proprietary joints to make 60-70 km cables.

After several more processes involving insulation and strengthening of the cables, they are tested for resilience and torsion. As a wind turbine’s nacelle rotates, the cables are severely twisted, so they must be extremely resistant to both torque and vibration. The torsion tests on cables simulate 20 years of use in a wind installation. Nexans said the exact test applied to a given cable depends on the customer’s specifications.

A Challenging Market

The wind industry’s move to deeper waters is challenging, according to Nexans, because transport vessels can only hold so much cable. Nexans’ flagship transport and laying boat, the Skagerrak, holds 50 tons of cable on its built-in turntable. The Skagerrak can accommodate 65 workers and has travelled all over the world. Not many vessels can hold its capacity, according to the company, and there are just one or two others in the world including the Giulio Verne, belonging to Nexans’ main competitor Prysmian.


The Nexans "Capject" can dig trenches in soft or hard sediments, according to the comany, and is able to operate in depths of up to 1,000 meters. Credit: Nexans.

With wind farms moving further offshore, said Vincent Dessale, chief operating officer of the submarine high voltage business line, Nexans’ customers are seeking increasingly higher transmission capacity, which means producing larger and longer cables. The Halden plant ran into problems in 2012, with an invoice delay in submarine cables leading to a drop in Nexans stock and an eventual restructuring of the business. The company has learned some lessons, it said, including that “feeding in more machines and manpower to match market demand is not sufficient” and that “coping with growing complexity and increasing timeline uncertainty requires highly structured organization, robust processes and the right mindset,” said Dessale.

Another challenge is that cables are becoming increasingly important in risk management. “One of the key differences between offshore and onshore wind farms, at the concept and design phase is the need to consider cable failure when designing the electrical architecture,” said David McNaught, senior engineer at consultancy Frazer-Nash. “If a submarine cable fails in service the consequences for the operability and profitability of the wind farm could be dire; especially if there are delays in securing a suitable repair vessel or if weather conditions are severe, likely during the winter months.

“It is essential that the electrical cable systems of wind farms have high reliability – that the system has the ability to withstand unforeseen circumstances,” McNaught continued. Cable risk is a relatively new aspect of wind project financial analyses, he said, but it is increasingly being considered – to the point where new guidelines from GL Renewables Certification, published in January, include on-site and power export cables. To address this growing concern, Nexans said it has scaled up risk analysis at the tendering stage and the company is working to develop and implement risk mitigation before beginning production.

Another challenge is transport for larger and longer cables.

The current Skagerrak, the third in its line and 130 km, was built in 1993; the Skagerrak 4, which is expected to be complete in 2014, will be 140 km.


Coils of cable at the base of the Nexans' 120-meter extrusion tower at the company's submarine high voltage direct-current (HVDC) cable factory in Halden, Norway. Credit: Nexans.

The market is growing in complexity, too, said Dirk Steinbrink, executive vice president for high voltage and underwater cables. The project scope of Nexans’ work has expanded to offer not just cables but turnkey interconnection solutions, he said.

On the Northwind project, which is expected to be completed before the end of 2013, Nexans is contracted to supply cables to connect the Belwind 2 offshore wind farm to Northwind, and Northwind to the shore. The project’s scope includes cable design, testing, supply, jointing termination work and on-site testing (called cable witnessing). The company said that it would use the largest cable ever manufactured at the project site, a 1-meter wide, 30-kg behemoth.

Offshore wind farm developers must also consider the social impact of the installation process. “The acceptance level from people living [near a site] is quite low,”   ??? >:( Steinbrink said. “They like green energy but don’t want to see us doing the work. So we do micro-tunneling, especially in places with tourism.”    ;D

Frédéric Michelland, senior executive vice president for high voltage and underwater cables, North and South America, does not expect the market for wind turbine cables to evolve dramatically over time. Today, he said, Nexans covers 80 percent of the European market, while “tomorrow that will move to North America and China – but we expect our market to remain largely European.” In Europe there are “still plenty of projects where most of the action will take place,” he said.

http://www.renewableenergyworld.com/rea/news/article/2013/12/subsea-cables-bring-offshore-wind-power-to-the-people




Within a 130 km of every major coastal city in the world is enough undersea current to power them many times over, at baseload quality 24/7,  immune to ocean surface storms, and with very low transmission losses due to the short distance from the harvesting point to the user. 
 



Leges         Sine    Moribus     Vanae   
Faith,
if it has not works, is dead, being alone.

AGelbert

  • Administrator
  • Hero Member
  • *****
  • Posts: 6654
  • Location: Colchester, Vermont
    • View Profile
    • Agelbert Truth AND Consequences
Re: Undersea Turbines
« Reply #2 on: June 06, 2014, 10:59:40 pm »

Friday, June 06, 2014
 
 
TIDAL POWER’S FORCE RISING IN SCOTLAND

Tidal Power — GE & Others Looking To Harness The Power Of The Moon   ;D
James Ayre, May 25, 2014 (Clean Technica)

“…[Tapping the energy of] tidal fluctuations caused by the movement of the [moon] has remained somewhat elusive…though, a number of interesting projects/approaches are being pursued…Scotland has been noted as possessing significant tidal resources that could meet up to 50% of its energy needs…GE Power Conversion is currently in the process of testing out new tidal turbine generators [on the sea floor near the Orkneys in Scotland]…[Turbines planned for the bottom of the Pentland Firth, a narrow channel that separates the Orkneys from the northern tip of Scotland… resemble large aircraft propellers submerged in 180 to 240 feet of water…[at strategic] ‘pinch points’ of the firth, where the tides rush in and out at the highest speeds…[T]idal power generation arrays will become much more common in the coming years, as the benefits of the technology are realized on a larger scale…The $1.2 billion [320 MW Swansea Bay Tidal Lagoon Project] is currently set to begin construction in 2015, with a completion date likely to be sometime in 2018…If the project is deemed successful, current plans are for the development of four more projects in other lagoons — which when all taken together would provide up to 10% of the UK’s domestic electricity needs…”

http://newenergynews.blogspot.com/2014/06/tidal-powers-force-rising-in-scotland.html


Leges         Sine    Moribus     Vanae   
Faith,
if it has not works, is dead, being alone.

AGelbert

  • Administrator
  • Hero Member
  • *****
  • Posts: 6654
  • Location: Colchester, Vermont
    • View Profile
    • Agelbert Truth AND Consequences
Re: Undersea Turbines
« Reply #3 on: December 05, 2014, 03:28:30 pm »
 
https://youtu.be/o8nezU0M7mI
Air and Ocean Currents

( to me!  ;D)

https://youtu.be/5tRiZG-yR24
Ocean Currents 1994 -2002 
« Last Edit: September 07, 2015, 05:27:52 pm by AGelbert »
Leges         Sine    Moribus     Vanae   
Faith,
if it has not works, is dead, being alone.

AGelbert

  • Administrator
  • Hero Member
  • *****
  • Posts: 6654
  • Location: Colchester, Vermont
    • View Profile
    • Agelbert Truth AND Consequences
Re: Undersea Turbines
« Reply #4 on: September 07, 2015, 05:24:14 pm »

Water, Energy and Waste Sustainable Development in Large Cities




There is no doubt that humans in general, and those concentrated in cities in particular, are responsible for much of the massive demand for potable of water and energy. There is also agreement that this demand is, at present not healthy for the biosphere in general and humans in particular. There is too much waste, inefficient energy use, lack of renewable energy infrastructure, pollution from fossil fuels and inefficient water use as well.

In summary, there is a consensus among knowledgeable and observant people in the reality based community that our present trajectory in the above issues is unsustainable.

The solution requires the phasing out of all fossil fuels and nuclear fission power plants and replace them with Renewable energy. This energy needs to be harvested within 100 miles or less from the highest energy users on the planet, the large cities, in order to have lower transmission and infrastructure costs.

The energy must be baseload quality 24 hours a day with wind and solar to supplement demand spikes along with pumped water storage energy, fuel cell or battery storage technologies.

The renewable energy source that is best suited on a global scale because it is constant, powerful and close to the major cities is the energy from ocean currents.

Observe the two maps below. 

World population concentration


Now let us overlay the Hydrosphere.  ;D


Please observe the result of the merging of the hydrosphere graphic and the population concentration graphic below:




The energy is renewable, does not disturb the biosphere or hydrosphere and can completely replace the polluting energy we now suffer from. The densely populated areas have this powerful source nearby. 

Ocean currents have far more energy potential than ocean tides. The tides alone are estimated to have a potential tidal stream energy capacity of over 120GW globally. Using both plus wind and PV would make a 100% Renewable Energy transition to the 18TW the planet required feasible with technology we now have.

Just in the UK alone, the marine power resource is estimated to be more than 10GW, representing about 50% of Europe’s tidal energy capacity.

In the USA a project is now in the works to provide wind turbine power to the East Coast for up to 1.9 million households. When built out, the Atlantic Wind Connection (AWC) backbone will stretch 350 miles off the coast from New Jersey to Virginia and will be able to connect 6,000MW of offshore wind turbines.



Now look at where those wind turbines will be and realize that undersea turbines can be placed close by and save on cabling the energy to the shore. Much more energy can be harvested 24 hours a day from the ocean current. Sharing energy transmission cables from wind and ocean current turbines will save millions of dollars and hasten the transition to 100% clean energy. 






As the new, clean energy replaces dirty energy, full electrification of the economies to eliminate the internal combustion engine for power plants, vehicles and factories will clean the air in large cities.

With plenty of renewable energy to electrify the planet and eliminate the internal combustion engine pollution, the worldwide potable water problem can be solved anywhere on the planet that the relative humidity is above 23% (any place it is not a desert climate) by extracting water from the ambient air.

The waste water can, given all the ocean current energy, be processed for agricultural fertilizer (eliminating petrochemical fertilizers).

In this way, we will imitate the biosphere in turning our waste into a nutrient that benefits all life on earth, not just humans.
 
https://youtu.be/WEe1bVjORN4

A. G. Gelbert





Leges         Sine    Moribus     Vanae   
Faith,
if it has not works, is dead, being alone.

AGelbert

  • Administrator
  • Hero Member
  • *****
  • Posts: 6654
  • Location: Colchester, Vermont
    • View Profile
    • Agelbert Truth AND Consequences
Re: Undersea Turbines
« Reply #5 on: September 07, 2015, 05:40:27 pm »
Rising sea levels will not affect our ability to harvest energy from Ocean Currents.

So, if we harvest a lot of our energy from the oceans, at least we won't be making things worse as the earth heats up. I always say that when you are in hole, it is prudent to stop digging. The ocean currents are available near most of the populated areas 24/7. We have the technology to tap that energy. This is not hard.

Here is some info on the physics of Ocean Currents. They leave out the rotation of the earth, which is behind MOST of the physics of ocean currents. But we would all be dead without rotation for many other reasons so I can understand why it such a given that it is not mentioned (i. e. assumed).

 
https://youtu.be/o8nezU0M7mI
Air and Ocean Currents


https://youtu.be/5tRiZG-yR24
Ocean Currents 1994 -2002 
Leges         Sine    Moribus     Vanae   
Faith,
if it has not works, is dead, being alone.

AGelbert

  • Administrator
  • Hero Member
  • *****
  • Posts: 6654
  • Location: Colchester, Vermont
    • View Profile
    • Agelbert Truth AND Consequences
Re: Undersea Turbines
« Reply #6 on: October 18, 2015, 02:47:09 pm »
Ocean Tides to Power More Than 150,000 Homes

Amanda Froelich, True Activist | October 18, 2015 12:09 pm

While the power plant below looks more like a gorgeous get-away than a solution to man’s energy needs, its benefits extend far beyond its beauty. As Reconstruct reports, the Swansea Bay Tidal Lagoon will use the rise and fall of ocean tides to generate enough renewable electricity to power 155,000 homes for 120 years.

The Swansea Bay Tidal Lagoon will use the rise and fall of ocean tides to generate enough renewable electricity to power 155,000 homes for 120 years. Photo credit: Preconstruct

Though not completed at present, when the structure is finished, it will produce enough electricity to displace more than a quarter million barrels of oil each year—while leaving virtually no carbon footprint.

Power plants have been generating electricity from the oceans’ tides since 1966, but the Swansea Lagoon is the first to employ a radically new method.

How Does It Work?  ???

It’s nearly six-mile-long barrier wall will enclose a huge amount of water in an artificial “tidal lagoon.” This lagoon captures and holds seawater at high tide. As the tide goes out, water in the 4.5 square mile lagoon will be as much as 27 feet higher than the water outside its walls. This immense pressure will be routed through 26 turbines, flooding out to sea until the water level equalizes on both sides of the lagoon.

The flow is reversed at high tide, keeping the sea out of the lagoon until it reaches maximum height. Then water is let go, so it may rush through the turbines until it again fills up the lagoon.

To put it into perspective, the amount of water rushing through the turbines would fill 100,000 Olympic swimming pools each day.

The Swansea Bay Tidal Lagoon will crank out clean energy as well as be used as a sports arena, aquaculture farm and seaside sculpture garden, reports GoodNewsNetwork. Its aquaculture farm will grow oysters, kelp and other local sea crops.

In addition, the lagoon can be used as a giant arena for sailing and cycling sports.

The designers of the fabulous structure plan to implement sculptures that appear to disappear into the water or rise out of it as the tides roll in and out.

Photo credit: Preconstruct

Its location at Swansea, Wales was chosen because it has some of the highest tide differences in the U.K. This will maximize the amount of water that can be used to turn turbines and generate the 420-gigawatt hours per year.

Plans for the structure were approved by the UK Energy Ministry in June, and construction is expected to begin sometime in 2017.

The builders are presently bargaining to exchange the $1.5 billion price tag (subsidized by the government for 35 years) for approval on two more tidal lagoon plants at Cardiff and Newport.

http://ecowatch.com/2015/10/18/ocean-tidal-lagoon/
Leges         Sine    Moribus     Vanae   
Faith,
if it has not works, is dead, being alone.

AGelbert

  • Administrator
  • Hero Member
  • *****
  • Posts: 6654
  • Location: Colchester, Vermont
    • View Profile
    • Agelbert Truth AND Consequences
Re: Undersea Turbines
« Reply #7 on: October 18, 2015, 04:07:46 pm »
I like that. While such extreme tides are pretty rare, there are some other places this could work out. Such an elegant design, the very antithesis of a nuke plant, don't you think?

The mean tidal range in Prince William Sound is 3m.  You might get a decent amount of electricity out of that.

However, how would all the Salmon get to their spawning grounds if you put one of those across the sound?

RE

RE,
Eddie is right and you are wrong. I know you will not accept that, but your premise that large tidal differentials are required for a "decent" amount of electricity is incorrect. A TINY difference, on a daily basis, is FAR more cost effective for electrical generation, and a LOT of it, than generating the SAME amount of power from fossil fuels. It hasn't been done BECAUSE the fossil fuel industry DID NOT WANT IT to be done. Thermodynamic efficiency and total required output had NOTHING to do with it.

But you can keep believing Gail Tverberg's BALONEY until the cows come home if you wish. You aren't known for altering your position on anything. You retreat into large fonts and repetition. You are a nice guy, RE. but you are as stubborn as they come.

Yes, I'm stubborn too.  ;D But I was a cornucopian three years ago, according to you. Now I'm too pessimistic, according to you. So tell me, old chum, who has failed to alter their position with new data, you or me?  ;)

There is only one thing to be said about the whole "fossil fuels are the best thing since toasted bread" BALONEY:

Dream on, fossil fuelers. The writing is on the wall for your CRAP. and it ain't gonna take 50 years for humanity to read it so you can keep trashing the planet and stuffing your empathy deficit disordered pockets. Have a nice day.

 


Here are the thermodynamic FACTS about Fossil Fuels versus PV Renewable energy (for those who can read them objectively):

Quote
Renewables have higher ERoEI than fossil fuels   

One the central claims of the peak oil/energy decline movement, is that renewable sources of power have extremely low ERoEI. Therefore, it is claimed, renewables are no substitute for fossil fuels, because they cannot provide enough “net energy” to power civilization. In support of this claim, energy decline adherents often post graphs like this one, showing that renewables (especially solar PV) have low ERoEI compared to fossil fuels. More recently, Hall and Prieto have published a book, Spain's photovoltaic revolution, in which they claim that the ERoEI of solar PV in Spain is only 2.45, which is far lower than the ERoEI of fossil fuels.

In fact, those claims are entirely wrong. Renewables have ERoEI ratios which are generally comparable to, or higher than, fossil fuels. Although peak oilers reach a different conclusion, that is because they are carrying out the calculation incorrectly. They are ignoring or not including massive waste heat losses (generally 60% or more) from combustion engines which drastically reduces the ERoEI of fossil fuels. Those waste heat losses provide no energy services to society, and should be counted as losses, but are wrongly counted as "energy returns" by peak oilers. Furthermore, peak oilers are ignoring or not counting other large energy losses of fossil fuels. Those omissions exaggerate the ERoEI of fossil fuels relative to renewables. When the calculation is carried out correctly, renewables have higher ERoEI ratios than fossil fuels.

In other words, the notion that renewables have ERoEI ratios which are lower than fossil fuels, is simply mistaken. It arises from performing invalid, apples-to-oranges comparisons, or from not counting energy losses of fossil fuels.


Fossil fuels have very low ERoEI ratios


Take this graph as an example. It compares the ERoEI of solar PV for electrical power, against the ERoEI of coal and gas for heat. That comparison is invalid, because it’s an apples-to-oranges comparison. Thermal power plants (like coal-burning plants) waste approximately 2/3ds of their energy as waste heat. Waste heat is radiated out into the atmosphere from the power plant, and provides no energy services to society. This massive energy loss from fossil fuels is not counted in that graph of ERoEI, thereby artificially inflating the ERoEI of fossil fuels. If we subtract the energy losses from conversion of thermal energy to electricity, then the ERoEI of fossil fuels declines by approximately 2/3rds relative to solar PV. Conversely, we could also increase the ERoEI of solar PV by approximately 3x, thereby providing an energy quality correction. As a result, the ERoEI for thermal power plants which generate electricity is approximately 2/3rds lower than the graph indicates, or (conversely) the ERoEI of solar PV is approximately 3x higher.

It’s simply meaningless to compare the ERoEI of electricity generation from renewables, against the ERoEI of heat from fossil fuels, because heat is an extremely low-quality kind of energy which is far less capable of performing work. This is an elementary principle of thermodynamics. In order to convert heat to work, we must lose the vast majority of that heat as waste. For example, the vast majority of energy from fossil fuels is simply rejected as waste heat from power plants or internal combustion engines, and so shouldn’t be counted as an “energy return” in ERoEI calculations.

In general, the ERoEI of fossil fuels is extremely low. Natural gas may have an ERoEI of 10, but that falls to 5 when considering the massive waste heat losses emitted from natural gas turbines (generally less than half of the energy in gas is converted to electricity). Coal may have an ERoEI of 30, but that declines to 10 when considering that coal power plants lose approximately 2/3rds of the energy of the coal as waste heat.

The ERoEI of oil is particularly low because it's used in inefficient internal combustion engines inside of vehicles. Most car engines lose about 80% or more of the energy from gasoline, as waste heat, when you include both engine and transmission losses. As a result, the ERoEI of energy which actually turns the wheels of the car (rather than heating the outside atmosphere) is not 14.5 for oil, as commonly claimed, but only 2.9.

Renewable sources of energy do not suffer from those tremendous losses. Although renewables sources of energy do suffer from power grid losses, those losses are minor (usually less than 5%).

As a result, the ERoEI ratios of renewable sources of power are often much higher than their fossil fuel counterparts. Wind turbines have an ERoEI of 18, compared to 10 for coal or 5 for natural gas. Solar PV panels powering battery-electric cars have an ERoEI of about 7 (deducting grid losses and recharging heat losses), compared to 2.9 for oil in gasoline-powered cars.

Incidentally, the extremely low ERoEI of oil for driving cars and trucks (2.9), refutes the notion that an ERoEI less than 8 would lead to the collapse of industrial civilization. That claim is extremely common in energy decline circles, but it was pulled out of thin air and was wrong to begin with for several other reasons. In fact, modern industrial civilization has been growing for decades (especially China and Korea) with ERoEIs far lower than 8.


Hall and Prieto’s criticism


More recently, a book by Hall and Prieto, has become all the rage in energy decline circles. That book claims that the ERoEI of solar PV is grossly exaggerated. Hall and Prieto adjust the ERoEI of solar PV downwards, by adding all kinds of incidental energy costs. They add every incidental energy cost they can think of, like the energy costs of building fences around the solar farm, and so on. They even add energy costs for things like corporate management, security, taxes, fairs, exhibitions, notary public fees, accountants, and and so on (monetary costs are converted into energy by means of a formula). Sometimes, their estimates of those costs are absurdly high. According to Hall and Prieto, the ERoEI of solar PV is only 2.45 when all those things are added.

Once again, the calculation is incorrect, and the comparison is invalid. Hall and Prieto are adding every incidental energy cost to solar that they can think of. However, such energy costs are not included in the ERoEI calculations of fossil fuels. For example, the ERoEI of oil does not include the costs of security in the middle east, or the costs of pipelines, tankers, tanker trucks, road wear from tanker trucks, construction of gas stations, energy costs of driving to the gas station to refuel, the highway patrol, and countless other things. If those costs were counted, then ERoEI of oil (which is already low, at 2.9, when including waste heat losses) would only decline further.

It's necessary to perform an apples-to-apples comparison here. If we're going to add up every incidental energy cost of solar PV, then we must perform the same procedure for oil. Only then would we have a valid comparison.

If you carry out a detailed accounting procedure for both solar and oil, then the ERoEI of oil will be even lower in comparison, than it already was. The incidental costs of oil are almost certainly higher than those for PV. Whereas oil is a scarce substance which requires massive extraction and transportation costs, silicon is the most abundant mineral in the Earth’s crust (sand, rocks) and does not require expensive or elaborate techniques of extraction or transportation. Whereas oil comes from unstable regions and requires massive security and military costs, silicon requires only a few security cameras. Whereas oil is subject to ongoing transportation costs, silicon needs to be transported only once during the lifetime of the solar cells. In general, the incidental costs of oil are far higher than those for solar PV. As a result, if we include those incidental costs in both cases, the adjusted ERoEI of oil will be even lower in comparison than it already was.

Again, when you perform valid, apples-to-apples comparisons, the ERoEI of solar PV is higher than that of oil or natural gas. Oil for transportation in cars has an ERoEI of only 2.9 (because of waste heat losses), but that is before we include incidental costs such as security, infrastructure, and so on, so oil’s total ERoEI would only decline, and would likely be lower than 2.

Hall and Prieto’s analysis is mistaken in other ways. Their estimate of 2.45 for PV is certainly far too low. They include things like taxes and land leases, which are not energy costs, but redistributions of money. Taxes provide services for society, so they should be counted as energy returns, not energy costs. If taxes in Europe on gasoline were counted as an energy cost, then the ERoEI of oil there would certainly fall to below 1. Also, Hall and Prieto include massive energy costs for premature retirement of solar cells because of rapidly advancing technology, but those cells won't be prematurely retired because they are paid for in advance and almost free to operate at that point, regardless of their efficiency compared to newer panels (newer panels would simply be added for future projects). Also, Prieto and Hall include things like administrative expenses, employees’ salaries, and so on, using a formula for converting dollars to energy which is far too high and is just wrong. You would obtain a far lower figure by converting salaries to energy using a more reasonable formula, of dividing the entire energy expenditure of a country by its entire GDP in order to obtain a conversion factor.

A correct calculation of the the ERoEI of solar PV including everything, would be more like 6, not 2.45. You can derive this figure by removing everything from Hall and Prieto’s analysis which is not an energy cost (such as taxes or land leases), and by using a more reasonable formula to convert monetary costs to energy.


Conclusions


In short. Renewables generally have higher ERoEI ratios than their fossil fuel counterparts. When you carry out a valid, apples-to-apples comparison, the ERoEI of renewables is generally better. This is because the ERoEI of fossil fuels is actually very poor--generally less than 5--when you correctly subtract the massive waste heat losses of combustion engines, and also subtract the massive incidental costs (such as security costs) of fossil fuels.

The only circumstance where fossil fuels have a higher ERoEI for renewables is when generating heat for smelting of ores or making cement or glass. That’s because such applications do not take place inside inefficient combustion engines, and so don't require subtracting the enormous waste heat losses of such engines. As a result, such applications still favor fossil fuels. Coal has a much higher ERoEI for this purpose than solar thermal plants, and (more importantly) is much cheaper. However, those uses are only a small fraction of total energy usage. Those uses will probably be the last energy uses which are converted from fossil fuels to other sources of energy, possibly more than 100 years from now.

Not that ERoEI matters much anyway. The whole idea is a mistake. What matters is the cost (in money) of net energy, for an energy source. If the cost of net energy is low, then the ERoEI is just totally unimportant. For example, if it were possible to build a 1 GW fusion power plant very easily out of duct tape for only $10, then it wouldn’t matter at all if it had an ERoEI of less than 2. We could just build more of them, and thereby produce the same amount of net energy as a higher-ERoEI (but more expensive) energy source. As long as an energy source has an ERoEI higher than 1, the ERoEI ceases to matter, and what matters is the total cost of net energy. This is discussed further here.

http://bountifulenergy.blogspot.com/2014/07/renewables-have-higher-eroei-than.html

No, I'm not going to bother with the BALONEY from those challenging this post here. At the link above I launched into a lengthy back and forth with a fossil fueler that, to his credit, managed to be polite even when he retreated into snark from lack of an argument. The fossil fuelers here have ZERO objectivity on this issue. I no longer feed the trolls here. You know who you are. Hang on to your wallets.   
Leges         Sine    Moribus     Vanae   
Faith,
if it has not works, is dead, being alone.

 

+-Recent Topics

Global Warming is WITH US by AGelbert
Today at 08:30:25 pm

Human Life is Fragile but EVERY Life is Valuable by AGelbert
Today at 08:05:17 pm

Member Interesting, Hair Raising, Humorous or Otherwise Unusual Experiences by AGelbert
Today at 07:52:06 pm

Electric Vehicles by AGelbert
Today at 07:37:23 pm

Non-routine News by AGelbert
Today at 06:57:14 pm

Mechanisms of Prejudice: Hidden and Not Hidden by AGelbert
Today at 04:49:03 pm

Corruption in Government by AGelbert
April 25, 2017, 10:31:05 pm

A High-Renewables Tomorrow, Today: by AGelbert
April 25, 2017, 08:50:44 pm

War Provocations and Peace Actions by AGelbert
April 25, 2017, 07:48:25 pm

Lost Cities and Civilizations by AGelbert
April 25, 2017, 07:08:21 pm

Free Web Hit Counter By CSS HTML Tutorial