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About this blog: Climate change, despite its outsized impact on the planet, is still an abstract concept to many of us. That needs to change. My hope is that readers of this blog will develop a better understanding of how our climate is evolving a...  (More)

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Is Offshore Wind a Reliable Renewable?

Uploaded: Jun 21, 2020
One of the big knocks against renewable resources is their intermittency. The sun doesn’t always shine, the wind doesn’t always blow. One way to see this is by looking at the “capacity factor” of solar plants and wind farms.

When you hear about renewable plants being built, you normally hear about the size of the plant in megawatts (MW). For example, our local power providers are building 100 and 200 MW solar plants, and Mountain View’s Googleplex gets power from the ~600 MW Altamont Pass Wind Farm. Those numbers reflect how much power the plant can generate at peak. If you multiply that power by time, you get a measure of the maximum amount of energy it can generate over a period of time. So, for example, if you were to run a 100 MW solar plant at full power for a year (that would be impossible because of night and clouds, but just pretend), then it would generate 100 * 365 * 24 = 876,000 MW-hours = 876 GW-hours (GWh) of energy.

In reality, the solar plant would not come close to producing that amount of energy in one year because the sun doesn’t shine 24x7. The “capacity factor” reflects the actual output of the plant compared to the maximum output. On average solar plants in California have a capacity factor of around 28%. That is pretty high for solar — California gets a lot of sun. On the east coast, the capacity factor for solar plants is more like 15-20%. (1)

The chart below shows the capacity factors of different types of energy in the US. (2)


This data is sourced from the U.S. Energy Information Administration

You can see that coal’s capacity factor (in black) has decreased substantially over the past ten years, despite many plant shutdowns. That is because the remaining plants are running less often as electricity markets prefer to run cleaner plants. This has made coal power more expensive. Gas plants (in red) have picked up some of the slack by running more often. But wind (in green) is also making improvements, and those are related more to technology than to market forces. Wind is becoming a more reliable resource.

You may be wondering how technology can make more wind power from the same wind. Well, computer models can help to better site (position) the turbines to capture more wind. A “yaw system” can dynamically rotate the turbine to face the wind, while a “pitch control” mechanism can swivel the blades to pick up more wind. But most importantly, taller turbines pick up higher, more reliable wind, and offshore turbines pick up steadier ocean breezes.


6 MW turbines in heavy seas off of Rhode Island’s coast. Source: National Renewable Energy Lab

Turbine improvements have driven big increases in capacity factors for wind farms. Europe’s onshore wind farms have a capacity factor of 24% because many turbines are smaller and older. The US’s wind farms are newer and have a capacity factor of 35%. Offshore wind yields another step up in reliability because the winds are steadier and ocean turbines can be taller. Europe’s offshore wind farms have an overall capacity factor of 38%, while the UK’s more recent offshore farms have a weighted capacity factor of 43%. GE has developed an enormous turbine for offshore use. It is around 60 stories high and almost as wide, with blades as long as a football field. GE claims it will achieve a capacity factor of 63%, and Time magazine named it one of its 2019 Inventions of the Year. That turbine can capture a lot of wind.

European countries have installed 5047 offshore turbines to date, including 502 in just the last year. The UK and Germany are leading in installed capacity. The US also has great potential for offshore wind, as you can see in the map below. Since around 80% of the nation’s electricity demand occurs in the coastal and Great Lakes states, this offshore power is conveniently situated. (3)


Source: Office of Energy Efficiency & Renewable Energy

Incredibly, the US has only five wind turbines offshore right now, located near Block Island off the coast of Rhode Island. In the last few years, though, the industry has gained momentum in the US, and there are commitments for 20GW of wind (3000+ turbines) in just the next five years.


Offshore wind farms planned in the next 5-10 years. Source: Bureau of Ocean Energy Management

One of the challenges we have on the west coast, and also in Maine, is that the ocean gets deep very quickly, so offshore turbines that are fixed into the ocean floor are not practical. Fortunately, floating turbines are being developed, and quickly, in part because oil and gas companies have considerable experience with this kind of technology. It is amazing to me that these not only work, but can work better than turbines built into the seabed. A journalist spoke with Po Wen Cheng, head of an international research project on floating wind energy at the University of Stuttgart, and relates that Cheng says that: “not only are winds in deeper waters more powerful than those closer to shore but the physics of the flexible, suspended rigs enables them to carry larger turbines. … Cheng argues that floating turbines could be even taller than today’s largest offshore rigs, perhaps with 400-foot blades and towers stretching nearly 1,000 feet into the air — as tall as the Eiffel Tower. Turbines of such dimensions could generate three times the electricity of today’s most advanced onshore turbines.” (4)


Some technologies used for floating wind turbines. Source: Wind Energies Technology Office

This is not just theoretical. A pilot floating wind project has been running very successfully off the coast of Scotland for several years. With five 6 MW turbines, it realized a capacity factor of 56% in its first two years of operation. To put that in perspective, that means each floating wind turbine generated 6 * 365 * 24 * 0.56 = 29,434 MWh of electricity per year. An average California home uses 6552 kWh per year. So a single one of those floating turbines could power 4492 typical California homes. Consider that the UK already has installed about 1900 offshore wind turbines. Suppose California were to install just 1500 turbines along our coast, newer models, say 8 MW on average with a good 50% capacity factor. That 12 GW of offshore wind would yield 53 TWh of energy per year, which is around 20% of California’s annual electricity consumption. That is an enormous amount of renewable energy.

Maine has seen the light and is going ahead with a pilot project of two 6 MW turbines. The Bureau of Ocean Energy Management analyzed six potential sites in California, predicting a capacity of 16 GW in just those areas. With the coastal winds coming on strong in the evenings just as our demand is ramping up and the sun is going down, it seems like a great complement to our solar power.


Six potential sites for offshore wind in California. Source: Bureau of Ocean Energy Management

And yet. California, for all its clean energy aspirations, has no pilots for offshore wind. No plans. Just long-lingering hopes. The obstacle is not birds, or marine life, or fishermen, or wealthy coastal dwellers concerned about aesthetics. It is not marine navigation, or even economics. Instead the major obstacle to offshore wind in California is the Department of Defense. According to the San Diego Tribune, “The U.S. Navy considers vast portions of California as ‘wind exclusion’ areas, including the entirety of Southern California.” Here is a map that the US Navy released about two years ago showing those areas in red.


US Navy map showing wind exclusion zones off the California coast. Source: March 12, 2018 US Navy Presentation to the California Energy Commission

The Navy is not leaving much room for offshore wind! A central coast Congressman, Representative Salud Carbajal, has been talking with the US Navy and others for years to find some way to establish offshore wind in his area. It is a great location, especially given ample transmission capacity from the demise of the Morro Bay gas plant in 2014 and (soon) the Diablo nuclear plant. But negotiations are slow going. A recent update from E&E News indicates that the Navy has offered to exchange a small area in return for a ban on many other areas. Among other things, the Navy is suggesting that wind could be built in the Monterey Bay National Marine Sanctuary. Carbajal, on the other hand, is suggesting that it would behoove the Navy to learn how to navigate around wind turbines given that so many other countries, including China, are erecting them along their coasts.

So, we’ll have to wait to see where California ends up with this very promising resource. Northern California may have the best shot in the short term. Change is disruptive, and change of the magnitude we need to see over the next 10-20 years is not easy. We see the tension across all forms of low-carbon energy, however promising they appear on paper. I applaud politicians like Carbajal who are really trying to make it work.

Notes and References
0. I will be taking the next few weeks off from this blog to do some summer activities. Happy Fourth of July!

1. The capacity factor of a solar farm is also affected by technology (e.g., whether the panels have tracking capability to better orient towards the sun) and market factors (e.g., how often the plant is called on to operate). Solar plants that need a lot of maintenance will also have lower capacity factors.

2. Nuclear energy is not shown in this chart. Nuclear has the highest capacity factor, at over 90%. Geothermal energy is also high, at around 75%, though there is much less of it.

3. This statistic and others can be found in this “top ten” list about offshore wind.

4. If you are wondering how such an incremental change in turbine size can make a 3x difference in electricity produced, it is because wind power is proportional to the cube of the wind speed. Engineers spend a lot of time tuning turbines (“orthodontics for wind farms”, as one writeup puts it) to increase energy production.

5. You can find a good overview of offshore wind in the US from the American Wind Energy Association. This report from the Office of Energy Efficiency and Renewable Energy has lots of information about US offshore wind plans.

6. This report has lots of data about wind energy (including offshore wind) in Europe.

Current Climate Data (May 2020)
Global impacts, US impacts, CO2 metric, Climate dashboard (updated annually)

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Comments

 +   7 people like this
Posted by Mrs. Wrongthink, a resident of Embarcadero Oaks/Leland,
on Jun 21, 2020 at 7:31 am



Nice post, but no thank you.


 +   9 people like this
Posted by Stephen, a resident of Duveneck/St. Francis,
on Jun 21, 2020 at 8:17 am

I suggest that you speak with Prof. Mark Jacobson at Stanford. He has worked/published extensively on this topic.


 +   3 people like this
Posted by California dreamin', a resident of Charleston Gardens,
on Jun 21, 2020 at 9:16 am

I'm in. How many would they be looking at near Morro, and how far offshore?


 +   21 people like this
Posted by Sherry Listgarten, a Palo Alto Online blogger,
on Jun 21, 2020 at 11:07 am

Sherry Listgarten is a registered user.

@Cal: Great questions. The proposed project at Morro Bay is for around 100 turbines at least 30 miles offshore. You can read more about it here.

@Stephen: I found some great content by Jacobson on this site for his upcoming book, though not much specifically on offshore or the politics of California's coasts. There is a lot of information on the technical details of how wind works, as well as the overall potential. I did realize this post has an oversight in that I should have discounted about 10% of a turbine's energy output for things like transmission and distribution losses before determining how many homes it could power.

One thing I found really interesting is Jacobson looks at the use of wind turbines at scale. For example, at some point we run out of wind if we deploy a billion or more turbines around the globe. What if we deployed 2-3 million, enough to power half of the world's energy needs? He looks at the impact on winds, evaporation, water vapor, temperature. Turns out it's fine, but what an interesting question to ask.

He also notes that offshore wind farms can blunt the impact of hurricanes like Sandy and Katrina. Plus they pay for themselves, unlike sea walls (which don't even slow down the wind). Interesting stuff! Thanks for the prompt to check it out...


 +  Like this comment
Posted by Sail On Sailor, a resident of Barron Park,
on Jun 21, 2020 at 1:01 pm

OK providing they do not present any maritime problems (i.e. disruption of shipping routes or safety issues due to potential
collisions/mishaps).


 +  Like this comment
Posted by CrescentParkAnon., a resident of Crescent Park,
on Jun 22, 2020 at 1:45 pm


> ... So, for example, if you were to run a 100 MW solar plant at full power for a
> year (that would be impossible because of night and clouds, but just pretend),
> then it would generate 100 * 365 * 24 = 876,000 MW-hours = 876 GW-hours
> (GWh) of energy.

I know this is an example, but it is misleading for those who might glance at
this and not look at it carefully.

> While solar panels may receive an average 7 hours of daylight per day, the
> average peak sun-hours may actually be closer to 3 or 4. Weather is also a
> factor. States like California or Florida can expect more clear and sunny days.

This means that the "24" in the example could be as low as 3, or 1/8th of
the 100 * 365 * 24 = 876,000 MW-hours = 876 GW-hours (GWh) of energy,
or around 110 GW-hours (GWh) of energy.

The largest solar plant in the world right now covers almost 16 square miles
of land. From Wikipedia, List of photovoltaic power stations: Web Link

Palo Alto is about 26 square miles, so this plant is about half the size of the
total area of Palo Alto.

Unfortunately I could not find a number on how much electricity the city
of Palo Alto uses, and nor is the actual output of that solar farm listed.

An example that took Palo Alto's electricity needs and translated that into
the area of a solar voltaic farm might be interesting. A lot of people seem to
have the mistaken impression that one can charge their car from a solar
panel on the car, so it would be instructive to show how much land area it
truly takes to charge just one electric vehicle - driven an average amount.

The wind information here is great, and wind is great for certain applications.
Particularly interesting is the off-shore wind farms that might actually afford
some cover for fish populations as well.

Solar and wind - with backup or batteries are temporary or partial solutions.
So if we rule out natural gas what else is going to supply to backup power,
and if whatever solution it is can provide reliable backup power, why not run
the numbers to see if it is the best solution supply our energy needs with
solar and wind as the backup to a more reliable and cheaper alternative?


 +   4 people like this
Posted by Mrs. Wrongthink, a resident of Laurel School,
on Jun 22, 2020 at 2:41 pm

Post removed, off topic


 +   14 people like this
Posted by Sherry Listgarten, a Palo Alto Online blogger,
on Jun 22, 2020 at 4:21 pm

Sherry Listgarten is a registered user.

@CPA: You can find out how much energy Palo Alto uses at this CEC website. You will see that in 2018 it was 890 GWh -- about 560 for commercial, 150 for industry, and 140 for residential (plus misc other).

You can find a list of California's solar farms and their output (see "Net MWh") at this CEC website.

If you are interested in how much land solar farms use, there is a high-level answer here. I know that you are a proponent of nuclear power, and one advantage of nuclear power is that it uses less space. However, some argue we have enough space to meet our needs with renewables. I haven't looked into it too much, but land use is certainly an important issue.

Finally, you may be interested in this just-released policy report from Berkeley that suggests that the plummeting prices of solar, wind, and storage mean we can get to 90% clean by 2035. Their report does incorporate substantial nuclear energy. The land use aspects are covered in Appendix 4, which isn't published yet.


 +  Like this comment
Posted by CrescentParkAnon., a resident of Crescent Park,
on Jun 23, 2020 at 3:52 pm

Post removed, off topic. I will be creating a nuclear sandbox for all of these comments on Sunday, so I will repost the content there.


 +  Like this comment
Posted by CrescentParkAnon., a resident of Crescent Park,
on Jun 23, 2020 at 6:10 pm

Post removed, off topic.


 +  Like this comment
Posted by California dreamin', a resident of Charleston Gardens,
on Jun 24, 2020 at 5:57 am

Post removed, off topic. I will be creating a nuclear sandbox for all of these comments on Sunday, so I will repost the content there.


 +  Like this comment
Posted by Stu Soffer, a resident of Menlo Park: Linfield Oaks,
on Jun 24, 2020 at 12:58 pm

Some years ago I researched the scope of clean tech patents. One surprise to me at the time was a Google patent for offshore power generation.


I have the presentation someplace. I recall I presented it to a bar association or American chemical society meeting in SF.


 +   1 person likes this
Posted by Albert K Henning, a resident of Duveneck/St. Francis,
on Jun 24, 2020 at 2:23 pm

Several years ago, I did the calculation for our home's energy needs. I used CPAU data from the prior five years, to find actual usage of energy from electricity, and from natural gas. I cast all the usage into units of kWh, for ease of comparison.

I then added an electric car, to replace our present gasoline-powered vehicle.

Our total annual energy use, including 10,000 miles on the car, came to 15,000 kWh.

Given our location, and using data available regarding number of sunny days, and hours per day, over the year; and, using easily available numbers for cost of a solar panel per kW, it's easy to buy enough solar panels to meet our complete needs for the year. The panels fit easily within our existing, available roof area.

The problem, however, is storage. Most of the energy generated occurs in summertime. Most energy consumption is wintertime (heat). There is no effective means, in terms of either cost or space/area, to store collected energy on-site.

Which raises the ongoing question of net metering. But that's a topic for another time. Bottom line, and in answer to some of the speculations above: it's easy to afford money and space to generate energy for residential use needs here in Palo Alto.

(Note: I'm not concerned about 'payback time'. We don't, in the US, calculate the true cost of energy, because we don't factor in the costs of carbon emissions. So, when I use the word 'afford', I'm speaking from an altruistic perspective, and not a strict-financial-payback perspective.)


 +  Like this comment
Posted by CrescentParkAnon., a resident of Crescent Park,
on Jun 24, 2020 at 9:41 pm

Post removed, off topic. I will be creating a nuclear sandbox for all of these comments on Sunday, so I will repost the content there.


 +  Like this comment
Posted by California dreamin', a resident of Charleston Gardens,
on Jun 25, 2020 at 5:56 am

Post removed, off-topic. I will be creating a nuclear sandbox for all of these comments on Sunday, so I will repost the content there.


 +  Like this comment
Posted by caseyc, a resident of Downtown North,
on Jun 25, 2020 at 11:06 am

caseyc is a registered user.

Sherry, Thanks for your informative climate blog. You've already filled in many blanks for us, obviously well researched. Looking forward to more of your reliable reporting and insights.


 +   5 people like this
Posted by Sherry Listgarten, a Palo Alto Online blogger,
on Jun 25, 2020 at 11:27 am

Sherry Listgarten is a registered user.

@Stu, that's interesting! I don't recall seeing anything about that. I did see that Google uses Deep Mind to scan weather reports, turbine operational data, and grid data to optimize when it put the energy from its wind farm onto the grid to better increase the value of that energy.

@Albert, that is super interesting. It sounds like you have a heat pump for your space heating? If you look at the capacity factor of solar farms by month, it looks like it varies by a factor of about 2.5x from the peak of summer to the nadir of winter. Your point about loads varying over time, as well as supply, is dead on. How should you size your solar panels given that? Batteries can spread the load out over the day, which helps. So excess in summer can go to the grid in afternoons when peoples' AC demands are high. But what to do with excess in spring, if you size panels to winter? It'd be nice if the panels could automatically shut off, because it costs our utilities to take that energy. (And as you may be suggesting, it'd be nice if net metering better reflected that.)

Anyway, thanks for sharing your experience. We definitely aren't yet at the point where 100% clean means no fossil. But offshore wind can help!

@Casey, thanks :)


 +   2 people like this
Posted by BobH, a resident of Palo Verde,
on Jun 25, 2020 at 12:29 pm

BobH is a registered user.

Sherry,

Interesting article. In your analysis of wind and solar, I think you were too focused on the “capacity factor". It is not a secret that there is no Sun at night, or that the wind doesn't blow all of the time.

The article doesn't mention of what happens when storage is added to the picture. Wind and Solar become much more viable when storage is included in a solution.

What Tesla has done in Australia is very interesting using batteries. I just saw an interesting article on water storage in Forbes:

Web Link

I think with local storage added, we can complete the move away from carbon based fuels for electricity generation.

Bob


 +  Like this comment
Posted by How might this affect birds?, a resident of Another Palo Alto neighborhood,
on Jun 25, 2020 at 1:14 pm

How might this affect birds? is a registered user.

Did you look at sea bird flight, feeding and migration patterns? How might these turbines affect them?


 +   1 person likes this
Posted by CrescentParkAnon., a resident of Crescent Park,
on Jun 25, 2020 at 3:22 pm

> Post removed, off topic. I will be creating a nuclear sandbox
> for all of these comments on Sunday, so I will repost the
> content there.

Sherry, Sherry, Sherry ... sorry if I am working your last
nerve in terms of trying to motivate even more rigor ( your
very informative and documented articles make a strong effort
to do that so I thought you would appreciate a contrarian
point of view if it was reasonable ) since it seems like you
mischaracterized my last comment in reply to Albert K Henning
about how easy solar was, to talk about or on paper as a
comment on nuclear which it was not.

What about all the questions I asked about Albert K Henning
solar comment? That is staking the argument ... I don't even
think I mentioned nuclear at all.

Please put that comment back in the context of this discussion
and allow it to proceed organically.

From my POV you are not this proactive at all when it comes
to people posting comments in rebuttal or attack for comments
made on other blogs. You simply haven't done it ... at
least to the extent you are censoring me here. It's your blog
I guess you can go the way of the two here who massively
censor all the time, I don't bother to post on any longer.

Again ... the comment I made in reply to Albert K Henning ...

Posted by CrescentParkAnon.,
a resident of Crescent Park, 0 minutes ago

15,000 kW-hrs per year, 15 megawatts, is about 41 kW-hrs/day.
CA has on average ( rounding up ) about 6 peak sunlight hours
per day.
To generate about 41 kW-hrs you need 7 kW per hour for those
6 hours.
( Every day, which you are not going to get on some days )
To generate 7 kW you would need 28 x 250 watt solar panels.
One 250 watt solar panel is about 16 sq-ft, so 28 panels would
be 450 total sq-ft. 450 sq-ft is a square about 21 feet on a
side.

I am not sure but, it seems to me that few houses in Palo Alto
have a south facing roof at the exact right angle and area
that could accommodate 450 sq-ft, 21'x21' or 11'x41' of solar
panels.

Yes, so you need an intermittent electricity source, or a
generator or storage for every watt you generate that you do
not use as you generate it, unless you have big time storage,
and then you have to take into account losses and upsize your
system.

You can in some places feed your solar into the grid, but you
still have a grid, and electricity generation going on somewhere
else, and that somewhere else has to be extremely flexible,
and probably running all night, and partially during the day.
I assume you are driving your electric car during the day,
right? Also, an electric car does not replace a gas-powered
car except for short city driving.

Forgive me if I am mistakenly interpreting the tone of your
comment as being that it is easy to go solar, but isn't that
what you said?

> Bottom line ...
• • •
> it's easy to afford money and space to generate energy for
> residential use needs here in Palo Alto.

Generating solar is great, but that is not the point - getting
off carbon based fuels is the point, and you conveniently and
completely left that out. If it is so easy, and you want to
do your share to end C02 generation, why don't you do it then,
and then report back to us on what kind of batteries you use,
how many you need, how much it costs and how often you have
problems or electricity deficits? Reality != paper.

Be sure to allow for short winter days, rainy days, occasional
dust cloud solar attenuation:
> Caribbean chokes on monster Saharan dust cloud headed
> toward the U.S.
> Kate Chappell and Sarah Marsh, Reuters, June 23, 2020
> KINGSTON/HAVANA (Reuters) - A massive plume of Saharan dust
> has shrouded swathes of the Caribbean, turning blue skies
> into a milky-brown haze and sparking health warnings across
> the region as air quality fell to unhealthy levels.

The US can be pushed into foolish decisions by loud and
mathematical, engineering and economically challenged into
eschewing the use of nuclear, but the rest of the world will
not. If we renounce
nuclear <<<<<<<<<<<<<<<<<<<<<<
we will be giving up a technology that we invented and
developed in order to fill the country with a complex
intermittent energy system that will just barely meet our
needs, and that will need redundancy from somewhere for a
very long time ... that means continued C02 generation.

What about the massive energy growth the world will need?

Right now we are close to the leaders of the world in
nuclear <<<<<<<<<<<<<<<<<<
technology. How many technologies can we just throw to
China and other countries and still retain the illusion of
being a world leader ... the fantasy?

>>>>>>>>>>>> OK, so I did peripherally mention nuclear, but
only as the one true carbonless steady source of energy -
it was not the gist or main point of my comment.

Also deleted was my comment that land, space on planet Earth
to cover with solar panels or wind farms is not a renewable
resource.

Should I even bother to post here and if not what does that
say about the CIVIL free flow of ideas and information?

Also, interesting choice of words, "sandbox". It generally
means isolating from the world ... so how in this case is that
different from censorship?

> In computer security, a sandbox is a security mechanism for
> separating running programs, usually in an effort to mitigate
> system failures or software vulnerabilities from spreading.
... In the sense of providing a highly controlled environment

Is this a highly controlled environment?


 +   5 people like this
Posted by Sherry Listgarten, a Palo Alto Online blogger,
on Jun 25, 2020 at 3:31 pm

Sherry Listgarten is a registered user.

Oops, sorry CPA, I over-deleted. I don't want to spend a ton of time on this -- I'm on holiday -- but I also don't want the comments here to turn into an endless and repetitive argument about nuclear between you and the other poster, as happens regularly. It. Is. Not. Helpful.

I'm posting your original comment here, but now this is kind of a mess. Please don't assume bad intentions. I'm just busy.

Again: Please, please, please stop posting about nuclear (as you do here again) on non-nuclear topics, or your post will be deleted. Not edited, I don't have time for editing.

I'm not picking on nuclear. I will generally get stricter about repetitive, off-topic, have-your-own-agenda comments, not just nuclear. It's just that nuclear seems to be the only one subject to that.

Your original post (minus some formatting):


15,000 kW-hrs per year, 15 megawatts, is about 41 kW-hrs per day. CA has on average ( rounding up ) about 6 peak sunlight hours per days. To generate about 41 kW-hrs you need 7 kW per hour for those 6 hours. ( Every day by the way, which you are not going to get some days ) To generate 7 kW you would need 28 x 250 watt solar panels. One 250 watt solar panel is about 16 sq-ft, so 28 panels would be 450 total sq-ft. 450 sq-ft is a square about 21 feet on a side. I am not sure but, it seems to me that few houses in Palo Alto have a south facing roof at the exact right angle and area that could accommodate 450 sq-ft, 21'x21' or 11'x41' of solar panels. But, I guess as long as you do, it's not a problem, right? Yes, so you need an intermittent electricity source, or a generator or storage for every watt you generate that you do not use as you generate it, unless you have big time storage, and then you have to take into account losses and upsize your system. You can in some places feed your solar into the grid, but you still have a grid, and electricity generation going on somewhere else, and that somewhere else has to be extremely flexible, and probably running all night, and partially during the day. I assume you are driving your electric car during the day, right? Also, an electric car does not replace a gas-powered car except for short city driving. Forgive me if I am mistakenly interpreting the tone of your comment as being that it is easy to go solar, but isn't that what you said? > Bottom line ... ... > it's easy to afford money and space to generate energy for residential use needs here in Palo Alto. Generating solar is great, but that is not the point - getting off carbon based fuels is the point, and you conveniently and completely left that out. If it is so easy, and you want to do your share to end CO2 generation, why don't you do it then, and then report back to us on what kind of batteries you use, how many you need, how much it costs and how often you have problems or electricity deficits? Be sure to allow for short winter days, rainy days, occasional dust cloud solar attenuation: Caribbean chokes on monster Saharan dust cloud headed toward the U.S. Kate Chappell and Sarah Marsh, Reuters, June 23, 2020, 12:14 PM PDT KINGSTON/HAVANA (Reuters) - A massive plume of Saharan dust has shrouded swathes of the Caribbean, turning blue skies into a milky-brown haze and sparking health warnings across the region as air quality fell to unhealthy levels. That probably doesn't matter since you don't live in the Caribbean though? The US can be pushed into foolish decisions by loud and mathematical, engineering and economically challenged into eschewing the use of nuclear, but the rest of the world will not. If we renounce nuclear we will be giving up a technology that we invented and developed in order to fill the country with a complex intermittent energy system that will just barely meet our needs, and that will need redundancy from somewhere for a very long time ... that means continued CO2 generation. What about energy growth? Right now we are close to the leaders of the world in nuclear technology. How many technologies can we just throw to China and other countries and still retain the illusion of being a world leader ... the fantasy?


 +  Like this comment
Posted by CrescentParkAnon., a resident of Crescent Park,
on Jun 25, 2020 at 3:39 pm

In terms of these massive offshore wind farms, is there any data that show how they would have fared in the Pacific tsunami?

In the midst of the COVID-19 global black swan event, is anyone considering what would happen if we made ourselves dependent on wind to a large degree, and then had a crippling even occur? How would we survive with the hit to our energy production, and how would be rebuild, or would we?


 +   6 people like this
Posted by Sherry Listgarten, a Palo Alto Online blogger,
on Jun 25, 2020 at 3:44 pm

Sherry Listgarten is a registered user.

@BobH: Thanks for the comment, and I agree that storage is important.

My interest in the capacity factor wasn't so much to reflect that renewables are intermittent. We all know that. It was to look some at the degree of intermittency, but more importantly to think about the fact that the degree of intermittency can be tuned and improved. That to me is interesting.

Yes, storage helps, but we don't have great storage options. Batteries as you know are neither renewable nor long-duration. Other options require a lot of space. Good seasonal storage is going to make someone a lot of money. In the meantime, we can save a lot of money and emissions by making renewables more reliable (and flexing demand).

Thanks for the link to the thermal storage article. Stanford offers (offered, most likely) tours of its system, if you are interested.

Hope this clarifies.

@Birds: I read that offshore is better than onshore wrt birds (sorry, don't have the reference), and while wind turbines and birds is a problem, you can see the scale of it here.


 +   1 person likes this
Posted by CrescentParkAnon., a resident of Crescent Park,
on Jun 25, 2020 at 3:51 pm

Post removed, off topic. I told you so :)


 +  Like this comment
Posted by CrescentParkAnon., a resident of Crescent Park,
on Jun 25, 2020 at 4:36 pm

Removed ad hominem post about "abuse of power".

Please see commenting guidelines.

All: note that commenter accidentally liked the above post. He would like us to know it was an accident.


 +   3 people like this
Posted by daydreaming, a resident of Charleston Gardens,
on Jun 25, 2020 at 5:35 pm

Portion removed.

> is there any data that show how they would have fared in the Pacific tsunami?

Portion removed.

It's my understanding that tsunamis are barely a ripple in the open water. Don't know about 30 miles offshore, off our 'shelf'.

Web Link


 +   2 people like this
Posted by Curmudgeon, a resident of Downtown North,
on Jun 25, 2020 at 10:45 pm

"In terms of these massive offshore wind farms, is there any data that show how they would have fared in the Pacific tsunami?"

They'd never notice it.


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Posted by Stu Soffer, a resident of Menlo Park: Linfield Oaks,
on Jun 27, 2020 at 5:24 pm

Stu Soffer is a registered user.

Sherry: If you send me your email I'll sen you my 2008 paper


 +   1 person likes this
Posted by Stu Soffer, a resident of Menlo Park: Linfield Oaks,
on Jun 27, 2020 at 6:45 pm

Stu Soffer is a registered user.

Sherry: See Google's Ocean data Center by Kurp
Patent application 20080209234


Web Link

Although this is using wave action.



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Posted by Sherry Listgarten, a Palo Alto Online blogger,
on Jun 28, 2020 at 11:31 am

Sherry Listgarten is a registered user.

Thanks Stu. You can find a link to email me at the top of this blog, near my byline and photo.


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