Windmills, Oilspills and Bird Deaths

[TimG]

Nonetheless the disappearance of nonrenewables will make their use inevitable.

It will make nuclear power inevitable. Wind - not so much.

[Bonam]

The whole term "renewable" is completely bogus in my opinion. However you are producing electricity, you are extracting that energy from the environment. Whether you are burning fossil fuels and thus releasing their stored energy, inducing fission in uranium to capture the energy released in fission reactions, or building a hydro dam to convert the kinetic energy of falling water into rotational motion of turbines. Solar panels, too, simply take energy that would have gone to heating the Earth (or being reflected back into space) and convert it into electricity, and wind power extracts energy from the wind, thereby lowering wind speeds downstream of the wind turbines.

Energy does not come from nowhere.

[dre]

"Renewable" doesnt mean that it doesnt come from the environment.

The term isnt bogus it makes perfect sense.

[Bonam]

"Renewable" doesnt mean that it doesnt come from the environment.

The term isnt bogus it makes perfect sense.

Using the term "renewable" gives people the impression that the energy is somehow endlessly "renewed". It is not. All energy comes from a finite source.

[TimG]

Solar panels, too, simply take energy that would have gone to heating the Earth (or being reflected back into space) and convert it into electricity

Solar panels need to be replaced over time.

Estimated number of Rooftop 3kW SolarPVs to meet world power needs in 2030: 1.7 billion

Estimate cost of Rooftop SolarPVs in 2030: $3823

Estimated lifetime of a solar PV: 20-30 years

Perpetual annual capital cost: $260 billion (i.e. every year 1/25 of panels need replacement - forever).

Annual energy delivered by panels (21% capacity factor): 9.3 billion MWh

Equivalent barrels of oil delivered: 5.2 billion barrels.

Equivalent cost of oil: $50 barrel of oil.

Source of solar cost data.

Energy conversion factors.

Now people presume the supply of solar is endless but replacing all of those panels every year consumes rare resources like indium. If we run out of that we cannot maintain the SolarPV infrastructure.

3KW systems are about 30 sq meters of solar panels.

That means 2 billion sq meters of solar panels are being disposed annually.

That is a lot of toxic waste for a renewable power source.

Edited July 9, 2010 by TimG

[dre]

Using the term "renewable" gives people the impression that the energy is somehow endlessly "renewed". It is not. All energy comes from a finite source.

Right but in terms of energies like wind and solar they are basically endless at least from a human perspective. The sun will keep shining and the wind will keep blowing for billions of years.

[TimG]

Right but in terms of energies like wind and solar they are basically endless at least from a human perspective. The sun will keep shining and the wind will keep blowing for billions of years.

See my post above:

Now people presume the supply of solar is endless but replacing all of those panels every year consumes rare resources like indium. If we run out of that we cannot maintain the SolarPV infrastructure.

3KW systems are about 30 sq meters of solar panels.

That means 2 billion sq meters of solar panels are being disposed annually.

That is a lot of toxic waste for a renewable power source.

[dre]

See my post above:

PV is only one way to use energy from the sun, and the technology is rapidly improving.

[Bonam]

Right but in terms of energies like wind and solar they are basically endless at least from a human perspective. The sun will keep shining and the wind will keep blowing for billions of years.

Yes, the sun will keep shining and the wind will keep blowing, but how much? If you put up a wind turbine, the wind downstream of that turbine moves slower, because some of its kinetic energy was extracted by the turbine. According to this extensive analysis of global wind resources, the total power available for extraction from the Earth's winds at low heights above the ground (where windmills operate) is 72 TW. That is about 5 times our current world human energy usage, as the article mentions.

However, what would happen if we actually built enough wind turbines to extract a substantial portion of that 72 TW? Well, we would be extracting all of that energy (and thus velocity) from the wind, effectively slowing/eliminating wind at these low altitudes. What effects would drastic reductions in low altitude winds have? For one, this could have disastrous environmental effects in terms of inhibiting reproduction of plants which reproduce by matter carried in the wind, elimination of wind patterns that circulate air between the polar and equatorial regions at low altitudes (causing massive climate change), air stagnation around cities (since it would no longer be swept away by wind), causing drastically reduced air quality and health problems, etc. Probably there are many more issues that no one has ever thought about.

So no, the wind won't just "keep on blowing" if we extract all the power out of it that keeps it blowing.

Now you might argue that we only need to build a few TW of wind power not 72, and that this would already be a big chunk of global energy production, but the point remains, wind is not infinite, is not "renewable", and every bit of energy that you take out of the wind is going to affect something - that energy that you took out of the wind to make electricity correlates directly to air that is moving slower than it otherwise would have been.

Similar arguments apply to solar. At any moment, the Earth is exposed to ~125,000 TW of solar power (about 90,000 TW after taking into account the Earth's albedo). Again, total current human energy consumption is small ( ~15 TW) compared to that, but it is growing rapidly over time. If we were to extract a significant portion of the 90,000 TW, which normally goes into heating the Earth's surface, oceans, and atmosphere, and instead converted that to electricity, we would be substantially altering the Earth's climate, reducing net heat flux into the Earth system, altering convective currents in the oceans and atmosphere, etc.

So the fact that the Sun will keep on shining for another 5 billion years is kind of irrelevant to the classification of wind and solar energy as "renewable". What matters is that if we use this energy, if we extract it from the wind or from the solar radiation flux hitting the Earth on a continual basis, we will alter the Earth's environment, potentially in ways comparably drastic to other forms of energy which are not considered "renewable", if we use enough of it.

Edited July 9, 2010 by Bonam

[TimG]

PV is only one way to use energy from the sun, and the technology is rapidly improving.

I could do the same calculations with others renewables. The fact is the capital infrastructure required for renewables does not last forever and no "improvements" in technology are not going change that. The cost of constantly replacing a huge infrastructure is comparable to the cost buying oil to produce the same amount of energy.

In fact, the cost of building the capital infrastructure for renewables will increase as the cost of oil increases which means the costs of renewables will rise - not fall as time goes on.

Edited July 9, 2010 by TimG

[Bonam]

I could do the same calculations with others renewables. The fact is the capital infrastructure required for renewables does not last forever and no "improvements" in technology are not going change that. The cost of constantly replacing a huge infrastructure is comparable to the cost buying oil to produce the same amount of energy.

In fact, the cost of building the capital infrastructure for renewables will increase as the cost of oil increases which means the costs of renewables will rise - not fall as time goes on.

However, oil itself is not free of the burden of infrastructure. It too requires wells, deep sea drilling, refineries, oil tankers, pipelines thousands of km long, etc. All this stuff is expensive as well.

[TimG]

However, oil itself is not free of the burden of infrastructure. It too requires wells, deep sea drilling, refineries, oil tankers, pipelines thousands of km long, etc. All this stuff is expensive as well.

Sure. But the capital infrastructure required per unit of energy produced is much smaller than the cost of per unit of energy for diffuse renewables.

[Bonam]

Sure. But the capital infrastructure required per unit of energy produced is much smaller than the cost of per unit of energy for diffuse renewables.

Perhaps. However, much of that may have to do with economies of scale and the maturity of the relevant technologies. Of course, not all of it, since "renewables" by their nature must be built over large and often remote areas, unlike the more cost effective technologies which can be built in large, centralized, facilities, which of course reduces costs. Notably, some solar power projects do call for large centralized facilities as well, including some that do not use photovoltaics (for example: http://en.wikipedia.org/wiki/Solar_power_tower).

Anyway, I do agree with your earlier statement that nuclear fission is really the inevitable solution to our energy needs, particularly in the medium term. In the long term, we will have better technologies, such as fusion.

[dre]

Sure. But the capital infrastructure required per unit of energy produced is much smaller than the cost of per unit of energy for diffuse renewables.

Thats if you compare oil technology in its current state which is after 100 years of development and utterly massive capital investment with technologies like wind and solar that in terms of capital are in their infancy.

[dre]

Yes, the sun will keep shining and the wind will keep blowing, but how much? If you put up a wind turbine, the wind downstream of that turbine moves slower, because some of its kinetic energy was extracted by the turbine. According to this extensive analysis of global wind resources, the total power available for extraction from the Earth's winds at low heights above the ground (where windmills operate) is 72 TW. That is about 5 times our current world human energy usage, as the article mentions.

However, what would happen if we actually built enough wind turbines to extract a substantial portion of that 72 TW? Well, we would be extracting all of that energy (and thus velocity) from the wind, effectively slowing/eliminating wind at these low altitudes. What effects would drastic reductions in low altitude winds have? For one, this could have disastrous environmental effects in terms of inhibiting reproduction of plants which reproduce by matter carried in the wind, elimination of wind patterns that circulate air between the polar and equatorial regions at low altitudes (causing massive climate change), air stagnation around cities (since it would no longer be swept away by wind), causing drastically reduced air quality and health problems, etc. Probably there are many more issues that no one has ever thought about.

So no, the wind won't just "keep on blowing" if we extract all the power out of it that keeps it blowing.

Now you might argue that we only need to build a few TW of wind power not 72, and that this would already be a big chunk of global energy production, but the point remains, wind is not infinite, is not "renewable", and every bit of energy that you take out of the wind is going to affect something - that energy that you took out of the wind to make electricity correlates directly to air that is moving slower than it otherwise would have been.

Similar arguments apply to solar. At any moment, the Earth is exposed to ~125,000 TW of solar power (about 90,000 TW after taking into account the Earth's albedo). Again, total current human energy consumption is small ( ~15 TW) compared to that, but it is growing rapidly over time. If we were to extract a significant portion of the 90,000 TW, which normally goes into heating the Earth's surface, oceans, and atmosphere, and instead converted that to electricity, we would be substantially altering the Earth's climate, reducing net heat flux into the Earth system, altering convective currents in the oceans and atmosphere, etc.

So the fact that the Sun will keep on shining for another 5 billion years is kind of irrelevant to the classification of wind and solar energy as "renewable". What matters is that if we use this energy, if we extract it from the wind or from the solar radiation flux hitting the Earth on a continual basis, we will alter the Earth's environment, potentially in ways comparably drastic to other forms of energy which are not considered "renewable", if we use enough of it.

Nobody is suggesting we need to get all our energy from a single source. Solar energy could power most of the worlds low rise buildings from their roof area alone, without increasing our contruction footprint at all, or stopping any more sunlight from hitting dirt than we do now. And thats with TODAYS technology which is already exponentially better than it was 10 or 20 years ago, and will continue to improve.

NOBODY is suggesting we cover as much of the earths surface with windmills and solar panels as youre describing. The future in energy will include a diverse energy generation paradigm with lots of different sources, and energy will not only be much more plentifull than ever before but also much cheaper.

[TimG]

Thats if you compare oil technology in its current state which is after 100 years of development and utterly massive capital investment with technologies like wind and solar that in terms of capital are in their infancy.

The basic laws of physics cannot be changed. These law impose hard limits on the size of the infrastructure required to collect the power. e.g. there is only 1366 watts/sqm of power coming from the sun and when you crunch the numbers you need a huge number of solar panels to get signicant energy from a source like that even if you assume no conversion losses. The numbers get worse for biofuels since photosynthesis is less than 10% efficient.

[dre]

I could do the same calculations with others renewables. The fact is the capital infrastructure required for renewables does not last forever and no "improvements" in technology are not going change that. The cost of constantly replacing a huge infrastructure is comparable to the cost buying oil to produce the same amount of energy.

In fact, the cost of building the capital infrastructure for renewables will increase as the cost of oil increases which means the costs of renewables will rise - not fall as time goes on.

No thats false. The cost of of wind energy for example has fallen dramatically in the last ten years even though the price of oil has drastically risen, and the costs of wind and other renewables will continue to plummet both due to advances in technology, and economy of scale.

[dre]

The basic laws of physics cannot be changed. These law impose hard limits on the size of the infrastructure required to collect the power. e.g. there is only 1366 watts/sqm of power coming from the sun and when you crunch the numbers you need a huge number of solar panels to get signicant energy from a source like that even if you assume no conversion losses. The numbers get worse for biofuels since photosynthesis is less than 10% efficient.

The laws of physics are not the barrier we are up against with renewables. Not even close. The barriers are technology and scale of production.

there is only 1366 watts/sqm of power coming from the sun and when you crunch the numbers you need a huge number of solar panels to get signicant energy from a source like that even if you assume no conversion losses

Right and your average rooftop of a lowrise residential dwelling is 50 - 100 sqm, way way more than you need to collect enough sunlight to power the home even with todays technology.

[Bonam]

Nobody is suggesting we need to get all our energy from a single source. Solar energy could power most of the worlds low rise buildings from their roof area alone, without increasing our contruction footprint at all, or stopping any more sunlight from hitting dirt than we do now. And thats with TODAYS technology which is already exponentially better than it was 10 or 20 years ago, and will continue to improve.

NOBODY is suggesting we cover as much of the earths surface with windmills and solar panels as youre describing. The future in energy will include a diverse energy generation paradigm with lots of different sources, and energy will not only be much more plentifull than ever before but also much cheaper.

I agree with all that, I'm simply arguing against the notion that these sources of energy (wind and solar) are truly "renewable". Sure, if we just use them on a relatively small scale, they may have no perceptible impact on the environment, but they are still limited and overuse of these resources can have substantial impacts, just as overuse of oil or other fossil resources also can have impacts.

When people first started using fossil fuels, the rate of usage also was so small that it may well have seemed that we could not possibly have any effect on the Earth's overall environment through such use or any foreseeable growth of use in the future (not that anyone likely gave it any thought at the time). But a few hundred years later we are using those resources in quantities thousands if not millions of times higher than we were then. Similarly, right now, our energy needs are far lower than what we could potentially get from wind/solar. But if we just decide to use these technologies and call it "problem solved", then in a hundred years (or perhaps less), when our energy needs have grown exponentially, we'd be facing the same issue once again, our overuse of those resources would be altering the environment in potentially undesirable ways.

So we just need to keep in mind from the beginning that no resource is truly "renewable", they are all finite (in the context of an Earthbound civilization anyway), and overuse of any resource, even those currently being advertised as clean and environmentally friendly, can have adverse effects.

Edited July 10, 2010 by Bonam

[TimG]

The laws of physics are not the barrier we are up against with renewables. Not even close. The barriers are technology and scale of production.

The laws of physics dictate the physical size of the infrastructure required to exploit the diffuse sources. This huge physical size makes renewables extremely expensive and 'scale of production' is not going to bring those costs down significantly because a large chunk of the installation cost is labour and transportation (which is why I believe that costs will increase as the price of oil increases).

Right and your average rooftop of a lowrise residential dwelling is 50 - 100 sqm, way way more than you need to collect enough sunlight to power the home even with todays technology.

It really depends on the home. If you have an air conditioner or electric heat then there is no chance of supplying your power with roof top solar. You also need a backup when the sun does not shine.

Hereis another guy who crunches the numbers.

In total, the European lifestyle uses 125 kWh per day per person for transport, heating, manufacturing, and electricity. That's equivalent to every person having 125 light bulbs switched on all the time. The average American uses 250 kWh per day: 250 light bulbs.

And most of this energy today comes from fossil fuels. What are our post-fossil-fuel options?

...

As a thought-experiment, let's imagine that technology switches and lifestyle changes manage to halve American energy consumption to 125 kWh per day per person. How big would the solar, wind and nuclear facilities need to be to supply this halved consumption? For simplicity, let's imagine getting one-third of the energy supply from each.

To supply 42 kWh per day per person from solar power requires roughly 80 square meters per person of solar panels.

To deliver 42 kWh per day per person from wind for everyone in the United States would require wind farms with a total area roughly equal to the area of California, a 200-fold increase in United States wind power.

To get 42 kWh per day per person from nuclear power would require 525 one-gigawatt nuclear power stations, a roughly five-fold increase over today's levels.

Edited July 10, 2010 by TimG

[dre]

The laws of physics dictate the physical size of the infrastructure required to exploit the diffuse sources. This huge physical size makes renewables extremely expensive and 'scale of production' is not going to bring those costs down significantly because a large chunk of the installation cost is labour and transportation (which is why I believe that costs will increase as the price of oil increases).

It really depends on the home. If you have an air conditioner or electric heat then there is no chance of supplying your power with roof top solar. You also need a backup when the sun does not shine.

Hereis another guy who crunches the numbers.

That guy is talking about powering your car or truck, and manufacturing done on your behalf. Im just talking about powering a low rise dwelling, which is already possible even with air conditioning or electric heat, especially if you live in an area where heat pumps work.

This huge physical size makes renewables extremely expensive and 'scale of production' is not going to bring those costs down significantly

Scale of production ALREADY IS bringing those cost down significantly. Look at the difference in the cost of PV today compared to ten years ago per watt. Its a fraction of what it used to be, and the reason for that is the technology is better... the panels are more efficient and use less specialized materials... and scale of production - they are making a lot more of them.

Same goes for an installed watt of wind energy. The prices are rapidly coming down, and we are NOT EVEN CLOSE to the bottom.

[dre]

I agree with all that, I'm simply arguing against the notion that these sources of energy (wind and solar) are truly "renewable". Sure, if we just use them on a relatively small scale, they may have no perceptible impact on the environment, but they are still limited and overuse of these resources can have substantial impacts, just as overuse of oil or other fossil resources also can have impacts.

When people first started using fossil fuels, the rate of usage also was so small that it may well have seemed that we could not possibly have any effect on the Earth's overall environment through such use or any foreseeable growth of use in the future (not that anyone likely gave it any thought at the time). But a few hundred years later we are using those resources in quantities thousands if not millions of times higher than we were then. Similarly, right now, our energy needs are far lower than what we could potentially get from wind/solar. But if we just decide to use these technologies and call it "problem solved", then in a hundred years (or perhaps less), when our energy needs have grown exponentially, we'd be facing the same issue once again, our overuse of those resources would be altering the environment in potentially undesirable ways.

So we just need to keep in mind from the beginning that no resource is truly "renewable", they are all finite (in the context of an Earthbound civilization anyway), and overuse of any resource, even those currently being advertised as clean and environmentally friendly, can have adverse effects.

Well from a scientific standpoint you are definately right. Even the sun isnt "renewable". In practical terms though the sun will keep producing energy for many billions of years so I think its fair enough to call solar energy renewable, which of course makes wind energy renewable as well. We arent ever going to "use these things up". You arent going to use a certain ammount of wind or light then it "runs out" like oil will.

But if we just decide to use these technologies and call it "problem solved", then in a hundred years (or perhaps less), when our energy needs have grown exponentially, we'd be facing the same issue once again, our overuse of those resources would be altering the environment in potentially undesirable ways.

I absolutely agree 100%. We need to keep developing energy technology. Nuclear, solar, wind, otec... ANYTHING that shows promise.

We have already fucked the dog for too long. The volatility in oil pricing has already become an impediment to economic growth... we should be 50 years ahead of where we are today in building the technologies and infrastructure that will power the next energy age.

We did EXACTLY what you just warned us not to do... when oil was plentifull we called it "problem solved" and stopped innovating.

[TimG]

Im just talking about powering a low rise dwelling, which is already possible even with air conditioning or electric heat, especially if you live in an area where heat pumps work.

Let's look at some data:

A "typical home" in America can use either electricity or gas to provide heat -- heat for the house, the hot water, the clothes dryer and the stove/oven. If you were to power a house with solar electricity, you would certainly use gas appliances because solar electricity is so expensive. This means that what you would be powering with solar electricity are things like the refrigerator, the lights, the compute­r, the TV, stereo equipment, motors in things like furnace fans and the washer, etc. Let's say that all of those things average out to 600 watts on average. Over the course of 24 hours, you need 600 watts * 24 hours = 14,400 watt-hours per day.

­From our calculations and assumptions abo­ve, we know that a solar panel can generate 70 milliwatts per square inch * 5 hours = 350 milliwatt hours per day. Therefore you need about 41,000 square inches of solar panel for the house. That's a solar panel that measures about 285 square feet (about 26 square meters). That would cost around $16,000 right now. Then, because the sun only shines part of the time, you would need to purchase a battery bank, an inverter, etc., and that often doubles the cost of the installation.

If you want to have a small room air conditioner in your bedroom, double everything.

The thing to remember, however, is that 100 watts per hour purchased from the power grid would only cost about 24 cents a day right now, or $91 a year. That's why you don't see many solar houses unless they are in very remote locations. When it only costs about $100 a year to purchase power from the grid, it is hard to justify spending thousands of dollars on a solar system.

So to install a system today with no heat, a/c or stove you need $16K. With a lifetime of 25 years you are looking at $640 per year for power. But the cost of the panels themselves is only about $2/Watt or $1200. The rest of cost is labour and other electrical components. So the cost of the PV panels could go to zero and it would still cost you $600/year for power that costs $100/year from the grid. There is absolutely no reason to believe that the cost of electrical components or labour will go down significantly in the future.

IOW, power prices would have to go up 6 times before you could possibly break even on the panels and that does not take into account the hassles of dealing with an unreliable power source. The bottom line is SolarPV will never be viable without subsidies. When fossil fuels run out nuclear power and large scale hydro will always be the cheapest alternatives.

Edited July 10, 2010 by TimG

[dre]

Let's look at some data:

So to install a system today with no heat, a/c or stove you need $16K. With a lifetime of 25 years you are looking at $640 per year for power. But the cost of the panels themselves is only about $2/Watt or $1200. The rest of cost is labour and other electrical components. So the cost of the PV panels could go to zero and it would still cost you $600/year for power that costs $100/year from the grid. There is absolutely no reason to believe that the cost of electrical components or labour will go down significantly in the future.

IOW, power prices would have to go up 6 times before you could possibly break even on the panels and that does not take into account the hassles of dealing with an unreliable power source. The bottom line is SolarPV will never be viable without subsidies.

Those numbers seem reasonable. We did an install on a house I built outside of grid coverage here and it actually cost over 50 thousand dollars. It includes heat though and AC through a heatpump.

There is absolutely no reason to believe that the cost of electrical components or labour will go down significantly in the future.

Actually most of those components are already coming down in price, and being improved by technology. They get cheap once more and more of them are being produced, and they are built by bigger producers in bigger facilities that buy materials in bigger quantities.

The bottom line is SolarPV will never be viable without subsidies.

No energy source is. I read you touting nuclear energy for example earlier in the thread, yet not a single nuclear industry in the world exists without massive subsidies and in most cases full or partial public ownership. Coal, gas, oil, hyrdoelectric... all those are subsidized, and have had literally endless ammounts of public capital pumped into them between the time they were first conceived and where they are now.

Youre also not factoring all the cost of infrastructure that would be made obsolete if lowrise building produced their own power. Billions of dollars of power lines, built on billions of dollars worth of property, and permanently maintained by an army of technicians.

The bottom line is that you wont know how solar energy compares with established sources of energy until its mature.

[TimG]

Actually most of those components are already coming down in price, and being improved by technology. They get cheap once more and more of them are being produced, and they are built by bigger producers in bigger facilities that buy materials in bigger quantities.

The problem is these components need materials like copper and steel. The components cannot be replaced with plastic or better chips - the way most cost reductions have been achieved with consumer products. This means there is a limit to the cost reductions that can be achieved. Also most of these kinds of components have been produced in mass quantities for decades for use inside factories so there is not as much room for improvement as you might think.

No energy source is. I read you touting nuclear energy for example earlier in the thread, yet not a single nuclear industry in the world exists without massive subsidies and in most cases full or partial public ownership.

Nuclear plants can be built on a commercial bais today with no subsidies and sell power at market rates. The only help the ask for in the US is loan guarantees because of the hostile regulatory environment.

Coal, gas, oil, hyrdoelectric... all those are subsidized, and have had literally endless ammounts of public capital pumped into them between the time they were first conceived and where they are now.

What matters is the subsidy per KWh of energy produced. They are nearly non-existant for those sources today and that is why they are economic.

Youre also not factoring all the cost of infrastructure that would be made obsolete if lowrise building produced their own power. Billions of dollars of power lines, built on billions of dollars worth of property, and permanently maintained by an army of technicians.

Not one inch of electrical grid will eliminated by residential solar PV because people will not want to go without power on cloudy days. They also will want a/c which cannot be supplied by solar PV.

The bottom line is that you wont know how solar energy compares with established sources of energy until its mature.

We know enough now. As I said, there are fundemental laws of physics that impose minimum size limits on the solarpv and the support infrastructure. The large physical size means transport and labour costs matter and do the costs of the raw materials like copper which are required to make the components. Edited July 10, 2010 by TimG