h a l f b a k e r yPlease listen carefully, as our opinions have changed.
add, search, annotate, link, view, overview, recent, by name, random
news, help, about, links, report a problem
browse anonymously,
or get an account
and write.
register,
|
|
|
Please log in.
Before you can vote, you need to register.
Please log in or create an account.
|
Using the right design, it may be possible to create solar hot water system that shunts a portion of the heat into spinning a turbine.
[solar hot water panel] ->[hot water tank]-> [steam] -> [generator]
Alternatively it could in the style of a mini 'solar thermal power plant' that shunts some heat
into a heat exchanger for hot water.
[solar thermal power plant panel] -> [ shunt to electric generator] -> [ heat exchanger] -> [hot water tank]
The last approach appears to be better as between the solar power plan panel and the heat exchanger, we can use liquids that can store more heat.
The pros:
-Better use of space as the same solar hot water system is being used to generate electricity.
-Possibly better efficiency as silicon tech is not yet as efficient compared to driving a mechanical generator.
-May be cheaper than buying solar hot water and solar panels combined.
Cons:
- More complexity
- May cost more (depends)
- Water may have to be stored pretty hot
(?) Baked
http://www.nuenergy...egrated/solarcombi/
[infidel, Dec 31 2011]
Again
http://www.energyma...icle&article_id=806
[infidel, Dec 31 2011]
[link]
|
| |
It's in the links, [Simpleton]. Try the second one
first. |
|
| |
simpleton:
Hmmmm... Good point? Well would changing the idea to make it a mini solar power plant that shunts some energy to heating water be a better idea? It can be done as part of a heat exchanger allowing us to regulate how hot the water can be. Might make the system more simpler. |
|
| |
I'll shall add that to the idea now |
|
| |
infidel:
We are trying to avoid the use of 'photovoltaic' as its not very efficient. |
|
| |
Use the heat to warm water and draw off some of
the energy using Peltier devices. |
|
| |
Peltier devices are not very efficient as well compared to a standard dynamo |
|
| |
Photovoltaics are as efficient as quite a lot of
gasoline engines. |
|
| |
really? I personally haven't heard of that infidel. From the last time I heard, was that photovoltaic efficiency was less than 20% |
|
| |
"the maximum efficiency is only around 80% for the best of these generators—60% is more typical" according to "Electric_generator" in Wikipedia |
|
| |
Very expensive PV can run upwards of 40% efficient, the
Carnot (theoretical maximum) efficiency of a gasoline
engine is maybe 60%. |
|
| |
A typical production PV cell is maybe 10-15%, a typical car
engine is maybe 20-40%. |
|
| |
That is an absolutely horrible way to look at it though. In a
car, you are paying for the fuel, so efficiency matters. In a
PV setup, the fuel is free, so initial cost matters. Efficiency
only matters when we start running out of space. |
|
| |
You're looking at this backwards: just rig a solar collecter-
type generator to run its cooling cycle through the water
heater. The oil has to cool down anyway, why not recover
the heat? |
|
| |
I based my comment on the fact modern
commercial
PV cells are at 18-20% and the bulk of cars are still
in
the range of 20% efficiency. There are more
efficient
cars, certainly. There are also more efficient PV
cells. It's a matter of cost and time as to how it
will
settle out. |
|
| |
You also have to consider, as [MechE] pointed out,
the sunk cost of PV vs gasoline energy usage, as
well
as the ongoing fuel cost. |
|
| |
[Akimbo], I recommended Peltier devices and PV
largely because there are no moving parts and
therefore much lower maintenance costs. Most of
the work you'll have to do after the event is
involved in cleaning the units to maintain
efficiency. |
|
| |
This is a poorly constructed idea, using poorly constructed
language. The subject has been covered extensively, can
we please move on? |
|
| |