solar sterling engine generators

[GreatBallofFire]

Stirling engine generators are definately the way to go if you want to spend $100,000 to generate $10 worth of electricity a month.

That has to be the most accurate description that I have ever read regarding the use of stirlings for generating electricity!

-Mark

[cssolar]

sterling generators

Hi Mark,

Take a look at the baxi eco gen unit it produces electric at the same time as heating water,

It is expensive but I guess when other companies start copying it prices will fall.

Tony

[russ]

Hi Mark,

Take a look at the baxi eco gen unit it produces electric at the same time as heating water,

It is expensive but I guess when other companies start copying it prices will fall.

Tony

Hi Tony - The micro-CHP is not really new - they can't make it economic is the problem. There are many wannabee suppliers of the units but without fantastic incentives the sales will be zero - similar to the Boombox (Bloombox) - a suckers game.

[GreatBallofFire]

Hi Mark,

Take a look at the baxi eco gen unit it produces electric at the same time as heating water,

It is expensive but I guess when other companies start copying it prices will fall.

Tony

Tony, thanks for the info, I will check it out. The problem I have with hybrid systems that generate hot water as a byproduct of generating electricity is that it always seems to end up with not enough electricity and lots of hot water. Usually these systems make very high efficiency claims, but that is only if ALL the hot water is put to use.

-Mark

[cssolar]

sterling generators

Hi Mark,
Yes I guess in a country with a hot climate, it wouldn't pay, but in the Uk it is quite cold and most houses use central heating ( mostly gas fired ) so at least in the winter some useful electricity would be generated.

Cheers

Tony

[billvon]

Hi Mark,
Yes I guess in a country with a hot climate, it wouldn't pay, but in the Uk it is quite cold and most houses use central heating ( mostly gas fired ) so at least in the winter some useful electricity would be generated.

Awful lot of moving parts for something that has to run close to full time.

Thermophotovoltaics is an alternative way to do that. If you already need a heat source you can do it without much additional heat input (waste heat is, after all, heat) and no moving parts to deal with.

[cssolar]

Hi Billvon,

Therphotovoltaics sounds interesting,

I am getting solar heated water at 85 degrees Celsius is that hot enough to convert into useful electrical energy.

I was thinking along the lines of a solar sterling generator, using vacuum tubes for the hot side and may be using very old technology for the cold side - porous clay cooling vessels ( they have been made here in Spain for hundreds of years for cooling water )

Any way everybody says it cant be done especially Russ !!

only joking Russ

Cheers Tony

[inetdog]

Awful lot of moving parts for something that has to run close to full time.

Thermophotovoltaics is an alternative way to do that. If you already need a heat source you can do it without much additional heat input (waste heat is, after all, heat) and no moving parts to deal with.

The efficiency and load capacity of thermovoltaics are both pretty miserable. But since you are dealing with waste heat anyway (assuming that the cost recovery would not be better by going to a condensing system for fuel-fed heaters), the question is whether the cost of the materials for thermovoltaic is justified by the amount of energy you get.

I have not looked at any evaluations of thermovoltaic with a solar source, but anything less than a 100 degree C temperature difference is pretty low to work with.

[billvon]

I am getting solar heated water at 85 degrees Celsius is that hot enough to convert into useful electrical energy.

Not via thermophotovoltaics. IF (big if) you want to heat cold water to 45C and you have lots of 85C water available you can use Peltier junctions to get a small amount of power (50-100 watts) during the heat transfer. They are expensive though.

I was thinking along the lines of a solar sterling generator, using vacuum tubes for the hot side and may be using very old technology for the cold side - porous clay cooling vessels ( they have been made here in Spain for hundreds of years for cooling water)

You'd need a lot of clay pots! An evap cooler (cooling tower) would be a lot more effective.

[russ]

Any way everybody says it cant be done especially Russ !!

only joking Russ

Cheers Tony

I worked with this stuff for a life time - at low temperatures and low delta T there is no driving force and units have to become immense to amount to anything.

Stack gas is often designed to be discharged at higher temperatures than necessary just because the cost of using the last 50 or 100

[GreatBallofFire]

Hi Mark,
Yes I guess in a country with a hot climate, it wouldn't pay, but in the Uk it is quite cold and most houses use central heating ( mostly gas fired ) so at least in the winter some useful electricity would be generated.

Cheers

Tony

Tony, there is nothing wrong with the design concept of stirling engines, but there are just too many other ways to accomplish the same goal for a lot less money. You can build the best horse drawn carriage in the world, but I'll stick to my car. Now maybe someday, someone might manufacture a version that is dirt cheap, long lasting, and physically small enough to be useful. Today is not that day.

-Mark

[GreatBallofFire]

For that matter, Google's green investments have generally turned up as losers to the best of my knowledge - they might be good at search engines but when they get out of their field they are even worse that they should be.

Russ

Google made the classic mistake of believing that people who could develop good algorithms and software code in the virtual word of computer programming could magically transition to the mechanical level with the same ease. My thinking is, the more minds working on problems the merrier, but the minds have to be based on the physics of the REAL world, not the virtual world.

-Mark

[walter69]

solar cooling

has anyone tried to use solar energy to refrigerate a sufficient amount of liquid, then when is cold - recirculate it and with use of a heat exchanger blow the cold air instead of an AC. That would eliminate a need to generate energy when it is less needed [during daylight] and store it for the peak hours [5PM to 9PM] in a large number of batteries?

[Sunking]

has anyone tried to use solar energy to refrigerate a sufficient amount of liquid, then when is cold - recirculate it and with use of a heat exchanger blow the cold air instead of an AC. That would eliminate a need to generate energy when it is less needed [during daylight] and store it for the peak hours [5PM to 9PM] in a large number of batteries?

No because it would be a huge waste of resources and terribly inefficient. You are basically saying I want to use and pay 20 times more for energy. Pretty much like using hydrogen or ethanol for fuel.

[Mike90250]

has anyone tried to use solar energy to refrigerate a sufficient amount of liquid, then when is cold - recirculate it and with use of a heat exchanger blow the cold air instead of an AC. That would eliminate a need to generate energy when it is less needed [during daylight] and store it for the peak hours [5PM to 9PM] in a large number of batteries?

you want an ammonia absorption refrigerator !

http://en.wikipedia.org/wiki/Absorption_refrigerator

Solar heat starts the cycle, and night time finishes it. Huge capacity, and equally huge risk if improperly engineered.