Renewable energy can replace coal

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Renewable energy can replace coal

 

I had to line up the various negatives of burning coal for energy before sharing this next link. I think each of these negatives highlighted deserve separate discussions, should anyone be willing. But there is an alternative to the current methods, methods causing disharmony amongst life on Earth. All we have to do is make the choice.

Really, it is all about capital and the return on investment. It is no secret the capital markets have financed the research and engineering of the modern fossil fuel and nuclear power generation plants. To the tune of billions. Now they want a return, a fat return. 

No doubt renewable energy is a roadblock to the desires of the super rich:

http://www.solarthermalmagazine.com/2011/01/25/battle-fo-dominance-between-renewables-coal-and-nuclear-likely-to-grow/

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Re: Renewable energy can replace coal

Sorry, that story sounds like a lot of nonsense to me.

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Re: Renewable energy can replace coal
james_knight_chaucer wrote:

Sorry, that story sounds like a lot of nonsense to me.

 

Why?

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Re: Renewable energy can replace coal

Okay, well to start with Sevenmmm, you are obviously anti-coal, as you have just started three separate anti-coal threads.

Here in the UK, we have a maximum of 5 GW of renewable energy from wind and hydro-power. It is also not very sunny for most of the year. In December we had two weeks of below zero temperatures. Daily average consumption around 50GW, but not a breath of wind. Average renewable output during those two weeks was 0.5GW, about half of which came from hydro-power, around 1% of consumption. It also was not very sunny, so photovoltaic is out.

So for two weeks, coal. gas and nuclear power kept the lights on. To replace those would thus require 200 times as many windmills as we have at the moment, that have taken us 20 years to erect. So for the next 40 years, we would have to put up 100 times as many windmills per year as we have done previously.

I don't think so.

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Re: Renewable energy can replace coal
sevenmmm wrote:
james_knight_chaucer wrote:

Sorry, that story sounds like a lot of nonsense to me.

Why?

Maybe I'm missing something, but here's one why. 

Extracted from the article:

Among other top line findings, the report demonstrates the need to phase out 90 percent of today’s coal and nuclear power plants by 2030 in order to have a stable and efficient electricity supply with 68% renewable sources by that date.

So I take nuclear and coal electrical generation out of the denominator and I am surprised that renewable sources now account for 68%?  What is the gap between electrical demand and electrical supply after 90% of coal and nuclear generation is gone.  Or are we supposed to be content with the fact that 68% of an inadequate electrical supply system is renewable?

Another why - adding a picture of a NUDET is a nice touch.  The drama of comparing uncontrolled nuclear energy release to controlled nuclear power generation while subliminally implying the risk of a NUDET from a power plant perhaps?  Greenpeace certainly has no agenda there right?  Cool

Other than that the article was interesting but a little short on details of how to accomplish the stated end state.  I'm still trying to figure out how the article apparently dismissed the demand side of things - unless it was tacitly stating that the supply level would establish the new demand level and everything would have to adjust down to the new level of consumption?

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Re: Renewable energy can replace coal
james_knight_chaucer wrote:

Okay, well to start with Sevenmmm, you are obviously anti-coal, as you have just started three separate anti-coal threads.

Here in the UK, we have a maximum of 5 GW of renewable energy from wind and hydro-power. It is also not very sunny for most of the year. In December we had two weeks of below zero temperatures. Daily average consumption around 50GW, but not a breath of wind. Average renewable output during those two weeks was 0.5GW, about half of which came from hydro-power, around 1% of consumption. It also was not very sunny, so photovoltaic is out.

So for two weeks, coal. gas and nuclear power kept the lights on. To replace those would thus require 200 times as many windmills as we have at the moment, that have taken us 20 years to erect. So for the next 40 years, we would have to put up 100 times as many windmills per year as we have done previously.

I don't think so.

 

Then, might I so so bold to type, if you consider me anti-coal, can I consider you pro-pollution for dismissing the continuing growth of mercury, sulfur dioxide, nitrous oxide, and CO2 emissions?

If I am anti-coal, are you then anti wind energy? How about photovoltaic and thermal electric? What is your opinion about conservation measures? Should the people of the world have access to all the pollution energy they desire? 

If no one makes a stand, then we will doom our progeny to one hell-of-a-transition once the Earth energy fund reads zero. I am making a stand, so you might just as well run along than waste your time making such a ridiculous assertion about my opinion concerning coal. You will always lose this debate...

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Re: Renewable energy can replace coal
sevenmmm wrote:

 

 How about photovoltaic and thermal electric? What is your opinion about conservation measures? Should the people of the world have access to all the pollution energy they desire? 

If no one makes a stand, then we will doom our progeny to one hell-of-a-transition once the Earth energy fund reads zero. I am making a stand, so you might just as well run along than waste your time making such a ridiculous assertion about my opinion concerning coal. You will always lose this debate...

 

I already told you. It is not sunny enough for photovoltaic in the UK winter. If by Thermal electric you mean geothermal heating, this still requires electricity and does not run lights or factories. If you mean generating steam by pumping water into the ground, our ground isn't hot enough. Conservation measures? Sure if you can conserve 99.5%, we might just scrape by on windmills. I think I won the debate.

By the way over here in Europe, we drive cars twice as efficient as the average American one because our petrol is the equivalent of $7/ US gallon.

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Re: Renewable energy can replace coal

Didjall listen to Kimosavvy's podcast on water? Solar is out.

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Re: Renewable energy can replace coal
james_knight_chaucer wrote:
sevenmmm wrote:

 

 How about photovoltaic and thermal electric? What is your opinion about conservation measures? Should the people of the world have access to all the pollution energy they desire? 

If no one makes a stand, then we will doom our progeny to one hell-of-a-transition once the Earth energy fund reads zero. I am making a stand, so you might just as well run along than waste your time making such a ridiculous assertion about my opinion concerning coal. You will always lose this debate...

 

I already told you. It is not sunny enough for photovoltaic in the UK winter. If by Thermal electric you mean geothermal heating, this still requires electricity and does not run lights or factories. If you mean generating steam by pumping water into the ground, our ground isn't hot enough. Conservation measures? Sure if you can conserve 99.5%, we might just scrape by on windmills. I think I won the debate.

By the way over here in Europe, we drive cars twice as efficient as the average American one because our petrol is the equivalent of $7/ US gallon.

 

UK has plenty of sun and photovoltaic produces electricty during cloudy conditions. Solar thermal has the means to store heat for night time and, if one wants to, build a high mass system that could conceivably store enough heat from the summer for the whole of winter. Of course, there is wind in the UK. With all of these measures taken into account, the UK could drastically lower coal burning for producing electricty and heating fuel use as well. 

All one has to do is make the choice.

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Re: Renewable energy can replace coal
Tycer wrote:

Didjall listen to Kimosavvy's podcast on water? Solar is out.

 

I live on the shores of Lake Michigan. 

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Re: Renewable energy can replace coal

James,

I'm confused. A solar system can indeed operate in the UK under supposed restrictive weather conditions. As a rough example, a six 110 amp battery bank charged solely by solar panels on a friends 70 foot by 10 foot 2 year old barge supports an 1800 watt pure sinewave inverter running a dishwasher, washing machine, microwave oven, plasma television, 60+ low energy ceiling lights, computer, and 5.1 surround sound system, without the engine being run as back up to support charge since October last year. It is of modern construction, cost half the price of a house of similar size in the beautiful location it is moored, is state of the art for £72,000, all in with light oak panel kitchen, hard wood floors and two bedrooms, perfect for his wife and two teenage boys.

All of the above can be applied to a house, converting most of its modern electrical requitements, running on a twelve volt system, all except for the washing machine, dish washer and microwave, which are run through the 240 volt inverter creating the most draw. The system complete was bought and fitted for well under £7,000. Of course the long term alternate choice is what exactly?

In the UK, gas prices are expected to rise by 9% over this next year. Keep that up for half a decade or so and the price of today will about double, even without taking into account (hyper)inflation. Coal here has doubled in price for household in just 7 years, with expectations that its price will double again in the following time-frame. Since 65% of electrical output here is from coal fired power, what keeps the lights on in the main in the Uk by 2030 is anyones guess with no major signs of political will, and an over all recessive capital investment in a grid system that will need a fairly extensive revamp by 2030. It'll be down to savvey individuals making personal investment to keep the lights on, or live like a ludite.

Choice ...

Sevenmmm,

Thankyou for the JOE (Joint Operating Environment) report as your signature. I'm halfway through reading it now. Put this link in along with your signature. It is indeed an important read.

Take Care,

~ VF ~

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Re: Renewable energy can replace coal

 

Quote:

As a rough example, a six 110 amp battery bank charged solely by solar panels on a friends 70 foot by 10 foot 2 year old barge supports an 1800 watt pure sinewave inverter running a dishwasher, washing machine, microwave oven, plasma television, 60+ low energy ceiling lights, computer, and 5.1 surround sound system, without the engine being run as back up to support charge since October last year. 

Then I think your friend is telling you porkies. The dishwasher and washing machine individually will use more energy than the 1800 watt inverter will produce.

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Re: Renewable energy can replace coal

James,

Oh, I see, still living in a world where every item I listed is running all at once, and with the most energy inefficient item listed drawing from supply. He and his family have obviously gained many years of knowledge and practical experience to not only run such a system, but to also build one that matches requirement.

Let me ask you now, what is the point of you writing on this forum if you can't add anything to discussion except what you feel isn't possible? Yes, I can keep writing back and forth with you for an eternity, but you know, if you're too damned ignorant to even hunt the net for advise, and are simply looking to others to confirm your ignorance as fact, I have neither the time or the patience ...

~ VF ~

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Re: Renewable energy can replace coal
Vanityfox451 wrote:

James,

you're too damned ignorant 

I'm ignorant? It's not me trying to break the laws of physics. Go and look at the rating plate of your own washing machine or dishwasher. I bet it uses more than 1.8kW.

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Re: Renewable energy can replace coal

James,

80+% of his system is running 12 volt, including the computer, sound system, television, DVD, lights, etc. This electrical draw plan table for off grid supply took me 30 seconds to find (as example). The inverter is used for no more than four hours on average over 268 hours (a week), with 12 volt as majoritive useage. All items that could be converted to 12 volt where possible have been, since for example, it is thoroughly stupid to run a DVD on its original 240 volt supply as a draw against an inverter, when inside the DVD there is a transformer converting 240 AC volts down to nearer 10 volts DC that can be bypassed with a couple of hours with a voltage tester and a soldering iron with basic understanding of electrical components.

You can read about KW output on the boring subject of washing machines in the UK here, and will find there are many that operate significantly under 1.8 KW.

Will you please do some homework before subscribing to the idea that it is impossible to live off-grid comfortably. I called you ignorant, not stupid. Compromise is a clue to a future with less ...

Rhare wrote an article that brought about a great deal of discussion a short while ago called Installing a Solar Energy System. Usefully DamnTheMatrix (Mike) runs a similar system with many added advantages over Rhare's, such as solar gain for keeping his house cool in summer, and warm in winter. You can read about Mike from this signature link at the base of his posts here.

~ VF ~

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Re: Renewable energy can replace coal

Seven,

           I certainly appreciate your thoughts on renewables. It is certainly what we will be left with at some point in the distant future. We might as well get started in earnest. Having said that, at this time renewables have a long way to go to replacing any sizeable portion of our energy demand. At my house, I offset all of my energy use with solar. No gas or oil for heat, everything is electric. My house is as efficient as we could possibly build it. The solar system to offset with batteries was about 100K. Furthermore, when it's sunny we produce around 80 KW per day, and when it's cloudy about 5-10 KW, and if it is really cloudy, we may only get 1 or 2 KW's. If I wasn't grid connected to my neighborhood coal plant, I would need another 10K in batteries that only last 10 years, and I would have to be more careful about what I do, and when. I actually think geothermal has a future. There is a plant in France that is still running from the early 1900's. The geothermal plants don't have to worry about the intermittancy of the power like solar and wind. However, as James said not everyone has access to good geothermal properties. Of course the real issue will be how we accomplish the massive build out that is needed in a world of declining resources and capital. Unfortunately, I just don't see it happening at a scale that will keep us in the lifestyle we have grown accustomed to.

Thanks

Phil  

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Re: Renewable energy can replace coal

These are just some of my own thoughts and opinions I wanted to apply to this thread ...

The US cannot and will not grow a sustainable energy supply that replaces the present system to support 311 million people, over or above the next twenty years. Half that population number, half it again and half that number again, and maybe, just maybe you'll come to a closer figure that may just possibly gain something close to a sustainable lifestyle that'll be a drop in the bucket compared to the circus ring of today.

 Combine huge and almost incomprehendable compromise then, against the collapsing present two thirds fuel import rate, present internal quantities in decline (unless the delusional idea that rock fracking with an EROEI at near one to one helps you sleep at night), and a lack of energy supported finance to build a replacement structure, let alone patch up the existing power grid ...

As with the essence of the 2005 Hirsch Report, it is simply too late to make anything like a clean bump-less splice with a project many thousand-fold above or beyond the size and scale of the Manhattan Project for example.

Almost six years after the completion of a two year study by Dr. Robert Hirsch, there still appears to be no public concensus, even though Hirsch reasoned cleanly with three points of reference : -

  • Waiting until world oil production peaks before taking crash program action leaves the world with a significant liquid fuel deficit for more than two decades.
  • Initiating a mitigation crash program 10 years before world oil peaking helps considerably but still leaves a liquid fuels shortfall roughly a decade after the time that oil would have peaked.
  • Initiating a mitigation crash program 20 years before peaking appears to offer the possibility of avoiding a world liquid fuels shortfall for the forecast period.

When you realise that Peak Oil was reached in 2006, and we're five years past peak by estimation, fully comprehended by many organisations, including the IEA (International Energy Agency), along with Dr. Chris Martenson ( our very own information scout and my reason for being at this fine site), you find it a compulsion to combine the ideas of personal energy security and sustainability when reading such articles as this one Chris Martenson wrote back in November 2010.

Which makes you wonder what the f*ck paying half of your wage taxation trying the futile and impossible task in securing foreign energy supply. Would it have been better to invest in alternatives as an entire nation well over twenty years ago? Cause and effect against a government on both sides of the political divide who are duplicitous with oil corporations, aka : name your politician/demagogue.

So : -

Am I talking here about making a soft landing and a splice to alternatives for the whole country? No.

Am I talking here about making a soft landing and a splice to alternatives for what ever whole State you live? No.

Am I talking here about making a soft landing and a splice to alternatives for what ever whole City you live? No.

Am I talking here about making a soft landing and a splice to alternatives for what ever whole Town you live? No.

Am I talking here about making a soft landing and a splice to alternatives for what ever whole Suburb you live? No.

Am I talking here about making a soft landing and a splice to alternatives for what ever whole Street you live? No.

I'm talking about individual means toward getting off of the grid, and even then I haven't mentioned the heightening awareness that a war over resources has been building powerfully for years (Iraq/Afghanistan for example??) and is very much on the immediate horizon.

Swallow hard and go back and digest the links above fully. I won't write about war here (maybe?), that's for another thread, but without all of these parametre's in place, what are competent conclusion, not for just now, but a year or a decade or two from now. What then???

~ VF ~

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Re: Renewable energy can replace coal
Vanityfox451 wrote:

 

You can read about KW output on the boring subject of washing machines in the UK here, and will find there are many that operate significantly under 1.8 KW.

 

 

No that is kWh. kwh is the total energy used per wash.

kW is related to the peak current drawn by the machine. Have you looked at your rating plate yet?

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Re: Renewable energy can replace coal
james_knight_chaucer wrote:
Vanityfox451 wrote:

You can read about KW output on the boring subject of washing machines in the UK here, and will find there are many that operate significantly under 1.8 KW.

No that is kWh. kwh is the total energy used per wash.

kW is related to the peak current drawn by the machine. Have you looked at your rating plate yet?

James,

The "reactive" load on the washing machine on the boat is well under 1300 watts, I've been informed. It is a custom built half load size, with a significantly lower rated motor fitted than original. The pure sine wave system is also 3kw, not 1.8kw as earlier stated, and 85% efficiency rated.

~ VF ~

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Re: Renewable energy can replace coal
zeroenergy21 wrote:

 

Seven,

           I certainly appreciate your thoughts on renewables. It is certainly what we will be left with at some point in the distant future. We might as well get started in earnest. Having said that, at this time renewables have a long way to go to replacing any sizeable portion of our energy demand. At my house, I offset all of my energy use with solar. No gas or oil for heat, everything is electric. My house is as efficient as we could possibly build it. The solar system to offset with batteries was about 100K. Furthermore, when it's sunny we produce around 80 KW per day, and when it's cloudy about 5-10 KW, and if it is really cloudy, we may only get 1 or 2 KW's. If I wasn't grid connected to my neighborhood coal plant, I would need another 10K in batteries that only last 10 years, and I would have to be more careful about what I do, and when. I actually think geothermal has a future. There is a plant in France that is still running from the early 1900's. The geothermal plants don't have to worry about the intermittancy of the power like solar and wind. However, as James said not everyone has access to good geothermal properties. Of course the real issue will be how we accomplish the massive build out that is needed in a world of declining resources and capital. Unfortunately, I just don't see it happening at a scale that will keep us in the lifestyle we have grown accustomed to.

Thanks

Phil  

Good. However, you would be much better served to replace PV electrical heating with a thermal system. These systems are approximately 60 percent efficient vs less than 20 percent with PV.

The types of thermal include an air system that simply draws the air from your house into the collectors, afterwhich a blower forces the heated air from the collectors and through a duct system. This is termed a negative pressure system. Insulated ducts can be installed through your attic or the basement sill. Controls can be added that connects to the thermostat in the house and switching the blower on when the temperature in the collectors reach a certain point, generally 90 degrees (F for you Euros).

The other system uses a non-toxic biodegradable anti-freeze mixed with de-ionized water to transfer heat from the risors in the collectors then through a heat exchanger in a water storage mechanism located within the thermal barrier of your house. This is a way to install more collectors than is needed during sun hours, banks the heat in the water storage, then releases the heat at a later time. In both systems I would recommend tinox-coated copper plates - in the collectors - as they generate the most heat, with copper being anti-microbial.

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Re: Renewable energy can replace coal

I'd have to dispute the notion PV works on cloudy days.  In two years of observation of our system, it doesn't do enough on cloudy days to overcome the inverter losses.  For all intents and purposes, you can forget PV in overcast, and even high Sirrus, light clouds cut production pretty seriously.  Best days we have are like today.....deep blue sky, no clouds all day.  A 20kw/hr day.

ACTUAL NUMBERS:

My system is: 3150w panel rated. 18 x 175w Solarworld panels. 2 FM60 charge controllers, a 1200amp/hr AGM battery bank, 2 GTFX2524 inverters ( [email protected]). This system is grid tied in normal mode, and switched to off grid when the grid is down ( the GTFX inverter has an extra contact that closes when the grid contract opens on grid down, and diverts power to where ever you have it wired to go.....transfer switch in my case )
The panels are mounted on two sets of home built single axis trackers. These help the panels produce about 20-25% more power over the course of time than fixed mount, based on what I have measured by turning off the trackers and leaving them in the 'noon' position. The horizon angle of the trackers is fixed at 37 degrees, my latitude.

Here are the production numbers for 2010:

Solar Kw/hr......Total Kw/hr used....$$

Jan---212...........1200...................55.07

Feb--149.............1854.................121.04

Mar--168.............2092.................141.92

Apr--203..............1813.................118.72

May--295..............865...................<0.26>

Jun--346...............679...................<4.20>

Jul--296................847....................22.20

Aug--366...............1132...................34.05

Sep--291................985..................37.59

Oct--407.................855...................4.03

Nov--339................757......................7.54

Dec--267.................664...................13.14

Total for year 2010: 3339 solar produced
Average per month: 278.25kw/hrs produced

Total used for 2010: 13,743
Average month: 1145kw/hrs

Total electric bills: $550.87
Average monthly bill: $45.91

NOTES:

1. This is my house, and my woodworking shop, and several farm buildings/etc. Some months I will run my dry kiln in the shop, and run the Kw/hrs up 200-300 for a month. (dehumidifier type kiln) It also depends on the amount of time I spend in the shop, several motors are 5hp on various machines, and the dust blower which runs with most machines is 3hp.

2. Also, we run stock tank heaters and chicken house heat in the winter, which tends to run the use up out of proportion to the year.

3. Being September, we switched to propane gas stove in the new kitchen, which will affect use some. Also switched to LED lighting in a major way. Also replaced older, energy hog fridge with new model that uses about 1/2 the previous Kwhrs.

4. We will run electric AC some in the summer, mostly July/August.

5. We get paid 12 cents OVER retail for all solar production ( TVA 10 yr contract ) Retail varies around 9 cents/kw/hr, depending on quarterly fuel adjustment, but is currently around 9 cents/kwhr. Amounts in <> reflect credit amount in our favor.

System cost about 20k, self installed.  About 13k after tax incentives. ( 30% Federal tax credit + small TVA cash payment )

Future expansion will be to add another 2450w of panels and one more charge controller ( FM80 ) to the system. That will max out what the two inverters will feed back to the grid, and should about double our annual production. (system becomes more efficient, first section "pays" the inverters loss )  Anticipated cost another 5-6k after incentives.

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Re: Renewable energy can replace coal
Vanityfox451 wrote:

Rhare wrote an article that brought about a great deal of discussion a short while ago called Installing a Solar Energy System. Usefully DamnTheMatrix (Mike) runs a similar system with many added advantages over Rhare's, such as solar gain for keeping his house cool in summer, and warm in winter. You can read about Mike from this signature link at the base of his posts here.

There are some pretty major differences between Mike's system and ours:

  • His house was built with solar in mind, not a retrofit like ours.
  • I believe his house is quite a bit smaller.
  • His house is in a more temperate climate - never freezes, which makes things much simpler.  In UK you would certainly have to have a much more complex system if your dealing with hydraulic thermal collectors.
  • We heat our house in winter with thermal collectors, generate domestic hot water all year round and we cool our house in summer by pulling heat from the floors and radiating it out at night.   If you are not in a retrofit situation you can use a lot of passive solar solutions which do provide advantages over active solutions such as ours.

I'm not sure I would say advantages as I would say different and built for the house and climate.

TNdancer wrote:

I'd have to dispute the notion PV works on cloudy days.

There is definitely a big drop on cloudy days, but we generally produce some.  Our worst day so far has been about 12kWh, versus our normal this week of around 60kWh (10.8kW system).  On the 12 kWh day there was 4" of snow on the panels and it was cloudy, so I was still pretty impressed that the system generated anything! SmileOur thermal system does not do well at all on cloudy days,  it builds up heat but generally not enough to be of any use.

sevenmm wrote:

Good. However, you would be much better served to replace PV electrical heating with a thermal system. These systems are approximately 60 percent efficient vs less than 20 percent with PV.

Very, very true:

1 Therm =  1.1 gal. propane = 29 kWh  - for us a flat plate collector generates about 1/2 T on a sunny day and a 225W panel generates about 1.25 kWh.  So it would take about 12 PV panels to equal one 4x10' flat plate panel.  Electric heat is very expensive, currently 1T of natural gas is about $0.55 and the equivalent electricity would be $3.48 (based on 0.12/kWh).

I also agree with zeroenergy21, we will not replace fossil fuels with solar (that includes thermal, PV, algae, bio fuels), there is not enough space, or resources to build out to cover current usage, not to mention few good storage options at this time.  The daily digest from 2/3 has quite a bit on this topic including some quick calculations that I figure it would take an area about the size of California with technology being deployed today to meet current US energy demand.

 

 

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Re: Renewable energy can replace coal
rhare wrote:

I also agree with zeroenergy21, we will not replace fossil fuels with solar (that includes thermal, PV, algae, bio fuels), there is not enough space, or resources to build out to cover current usage, not to mention few good storage options at this time.  The daily digest from 2/3 has quite a bit on this topic including some quick calculations that I figure it would take an area about the size of California with technology being deployed today to meet current US energy demand.

I believe future demand will be much less than today! One way or the other...Cool

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Re: Renewable energy can replace coal

Rhare,

I didn't write that to have a dig at you.  It is simply my opinion that if given the choice, I would neither have bought your house, and would not have chosen the location you live in. If I already lived in the house in the location it was in, and with the knowledge I now possess, I would have sold your house, moved elsewhere (more likely New Zealand), and with the money gained from the sale, bought a good size strip of land and built something that mirrors Mikes house - small, efficient and much more simplified than your own.

When applying such things as circumstance, such as close family and friends, a community known to me for many years, and real estate values making my home impossible to sell, I would make do with what tools I had at my disposal. If I then was the owner of your house, with a wife and family of small children to protect, maybe I would have ended doing what you have, only with plenty of partition walls for heat trap, and a great deal more simplified...

~ VF ~

 

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rhare
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Posts: 1329
Re: Renewable energy can replace coal
Vanityfox451 wrote:

When applying such things as circumstance, such as close family and friends, a community known to me for many years, and real estate values making my home impossible to sell, I would make do with what tools I had at my disposal.

Exactly the choice and what we did.

Vanityfox451 wrote:

maybe I would have ended doing what you have, only with plenty of partition walls for heat trap, and a great deal more simplified...

I have contemplated ways to seperate the rooms a bit more, but I'm not sure what could have been done to make the system any simpler since it's not very complex (large but not overly complex).  If you want "battery backup" you have 2 choices, tradition DC coupled or AC coupled (our choice).  I actually think AC coupled is a bit simpler and can be added to existing grid tied systems.

For thermal, the system is quite simple, no large storage tanks and not much different than a traditional radiant/DHW system that uses a single boiler (many do).  I'm truely curious what you would have done to make it simpler?  We did put a computer control instead of traditional relays in place since it gave us a lot more flexibility in the system, but that was not so much of an addition in complexity as a trade off in methodology (software versus hardwired controls).

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Vanityfox451
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Posts: 1636
Re: Renewable energy can replace coal

Rhare,

Let me take a sideways approach to this. If you look in the top right hand of this post, you'll find I became a registered user on the 28th December 2008. I'd read just about every previous post on the site up to that date from the 29th of August 2008, when I stumbled upon Dr Chris Martenson's Crash Course through a prolific blogger called The Modern Mystic on You Tube, with this film : -

Over the last roughly two and half years then, I've watched posters come and go. Many, I've come to note, just come here and postulate about stuff they haven't grasped so as to bitch, many enjoying the benefit of witnessing this global bus crash from a comfy seat with popcorn.

In that time span, I've read and digested a book about every 5 days and watched 100's and 100's of films both short and long, a few of which I've posted on a thread I now never seem to find the time to add more to, called : Important films, books or internet pages we all should study - Add your own - forward of this post here.

What am I trying to say ...

Rhare, there are not many people here who not only talk the talk, but walk the walk, getting off their ass and doing something. Not only doing something, but sharing the experience of it practically. You've done this. You've built your home while others dream of the idea.

What is perfect? What is perfection? One mans meat is another mans murder.

I don't agree with everything you write, but would you want me to? You don't agree with everything I write, I wouldn't want you to either. But we can smash out so much focus from opposing viewpoints, and come to fantastic conclusions that would never have been gained on our own and without the other.

I'm impressed with what you've achieved. You've created something that everyone could do if they only had the drive and passion to attain it. Time though, is no friend, and from what I see, most are going to lose against time with the shortening gap between now and what is coming around the pike.

So, perfect then what you have as best you can, with the tools you have. You're a brave man, and I couldn't judge you or prove you otherwise ...

~ VF ~

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sevenmmm
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Re: Renewable energy can replace coal
rhare wrote:

 

I have contemplated ways to seperate the rooms a bit more, but I'm not sure what could have been done to make the system any simpler since it's not very complex (large but not overly complex).  

The only way this works is if those walls become a thermal barrier. To better explain, if you shut the heat off to a part of your house within the thermal barrier, you will think you are saving energy because those rooms are cooler. But in reality, the heat in your chosen rooms can easily be transferred through the unisulated walls into the closed sections. So here, once the temp finds the level (you may save a therm in the drop), just as much heat will be transferred to the closed rooms as if you've left them heated.

You can't cheat the 2nd Law.

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rhare
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Posts: 1329
Re: Renewable energy can replace coal
sevenmmm wrote:

But in reality, the heat in your chosen rooms can easily be transferred through the unisulated walls into the closed sections.... just as much heat will be transferred to the closed rooms as if you've left them heated.

Not buying that.   Yes you have heat transfer, but just an internal wall with sheetrock and air gap in between does a pretty good job of insulating.  After all your only talking maybe 20 degrees heat differential (but that 20 degrees can make a big difference in your bill).  It takes time for heat to migrate between rooms. We have 8 zones and can already segment rooms pretty well. With the our solar installation I can choose to only heat some rooms with solar energy and others augment them with a boiler.  Even rooms with no walls seperating them I can tell a dramatic difference in heat in the different areas.  Does it spill over, of course, but even a curtain between rooms stops convection from circulating air between a heated room and an unheated room.

 

 

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sevenmmm
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Posts: 108
Re: Renewable energy can replace coal
rhare wrote:
sevenmmm wrote:

But in reality, the heat in your chosen rooms can easily be transferred through the unisulated walls into the closed sections.... just as much heat will be transferred to the closed rooms as if you've left them heated.

Not buying that.   Yes you have heat transfer, but just an internal wall with sheetrock and air gap in between does a pretty good job of insulating.  After all your only talking maybe 20 degrees heat differential (but that 20 degrees can make a big difference in your bill).  It takes time for heat to migrate between rooms. We have 8 zones and can already segment rooms pretty well. With the our solar installation I can choose to only heat some rooms with solar energy and others augment them with a boiler.  Even rooms with no walls seperating them I can tell a dramatic difference in heat in the different areas.  Does it spill over, of course, but even a curtain between rooms stops convection from circulating air between a heated room and an unheated room.

http://www.mansfieldct.org/schools/mms/staff/hand/convcondrad.htm

An excerpt to this link:

Conduction is the transfer of energy through matter from particle to particle. It is the transfer and distribution of heat energy from atom to atom within a substance. For example, a spoon in a cup of hot soup becomes warmer because the heat from the soup is conducted along the spoon. Conduction is most effective in solids-but it can happen in fluids. Fun fact: Have you ever noticed that metals tend to feel cold? Believe it or not, they are not colder! They only feel colder because they conduct heat away from your hand. You perceive the heat that is leaving your hand as cold.


The first link is taught to grade school age children, the next one is for homeowners!

 

http://www.savehouseholdenergy.com/energy-loss.html

An excerpt:

Conductive heat transfer refers to heat that transfers through your walls, as opposed to the heat that might pass around the walls through cracks. In this type of heat transfer, there is a molecule-to-molecule transfer of energy. Or, as my old heat chemical engineering textbook states: "Heat is conducted by the transfer of energy of motion between adjacent molecules" 1. As an analogy, this would be like pushing a person on one side of a very crowded room and having that person bump into the person next to them, resulting in that person bumping into the next person, and so on, resulting in someone on the far side of the room being moved. Conductive heat transfer is governed largely by your R-values in your walls. So, if you have uninsulated walls or walls with poor R-value, it is very easy for heat to pass through.

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Damnthematrix
Status: Diamond Member (Offline)
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Posts: 3998
Re: Renewable energy can replace coal
TNdancer wrote:

I'd have to dispute the notion PV works on cloudy days.  In two years of observation of our system, it doesn't do enough on cloudy days to overcome the inverter losses.  For all intents and purposes, you can forget PV in overcast, and even high Sirrus, light clouds cut production pretty seriously.  Best days we have are like today.....deep blue sky, no clouds all day.  A 20kw/hr day.

Depends where you live......  Here in Australia, 26 degrees S, the very worst result ever from our 3.5kW system has been 3 kWhrs.  On the other hand, it's interesting that your system which is smaller than ours produces more power on sunny days, obviously because our panels get much hotter than yours and thus derate more significantly.  20 kWhr is the very very best result we ever got, normally 17 - 18 in clear skies.

I believe it is important to match the available natural resources with the right technology.  Often, as you get further from the equator and the sun isn't great, good wind resources are available.  The opposite is true here.  I'd still consider a turbine here if I had the money, but I certainly wouldn't put up a big expensive one, when the 3.5 kW system here ALWAYS garantees we generate everything we need for a whole 24 hours.  Rain hail or shine.

As usual, it's horses for courses.  You can check out what we installed on my blog linked at the foot of this message.

Mike

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Damnthematrix
Status: Diamond Member (Offline)
Joined: Aug 10 2008
Posts: 3998
Re: Renewable energy can replace coal
rhare wrote:

There are some pretty major differences between Mike's system and ours:

  • His house was built with solar in mind, not a retrofit like ours.
  • I believe his house is quite a bit smaller.
  • His house is in a more temperate climate - never freezes, which makes things much simpler.  In UK you would certainly have to have a much more complex system if your dealing with hydraulic thermal collectors.
  • We heat our house in winter with thermal collectors, generate domestic hot water all year round and we cool our house in summer by pulling heat from the floors and radiating it out at night.   If you are not in a retrofit situation you can use a lot of passive solar solutions which do provide advantages over active solutions such as ours.

Most of what you wrote here is precisely why I wouldn't retrofit a big badly designed house......

BTW, it does freeze here, though not regularly and certainly no snow, but on the other hand we also get 100+ degree periods that have been known to last two weeks at a streetch.... and I still manage to neither cool nor heat.

We are seriously thinking of moving to either Tasmania or New Zealand within the next two to five years....  I can't stand the heat, and Climate Change here is terrifying the willies out of me.  I believe I could design a house that would require no heating at all in those climates without any complicated active systems.  It's all about thermal mass, and siting....  siting and sizing windows in particular.  We would probably also have to go to double glazing, something we never use in the sub tropics.  I already have a plan in my head.  Remember the Swiss house dug into the hillside...?? It's partly my inspiration.

Mike

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