|
Setting a programmable thermostat
Is the "cool setpoint" the temperature when the air-conditioner goes
on? Is the "heat setpoint" the temperature when the heater goes on? Should the "cool setpoint" temperature be higher than the "heat setpoint" temperature? |
Setting a programmable thermostat
"gcotterl" wrote in message ... Is the "cool setpoint" the temperature when the air-conditioner goes on? Is the "heat setpoint" the temperature when the heater goes on? Should the "cool setpoint" temperature be higher than the "heat setpoint" temperature? It is actually the temperature they go off as the set temperature is met. I know what you mean though, one is for winter heating, the other for summer cooling. Most thermostats have to be moved from heat to cool so if that is the case, the actual set temperature does not matter. If yours is fully automatic, then yes, the heat is below the cooling number In some industrial applications it is possible to run both heat and AC at the same time to get humidity control. |
Setting a programmable thermostat
gcotterl wrote:
Is the "cool setpoint" the temperature when the air-conditioner goes on? Is the "heat setpoint" the temperature when the heater goes on? Should the "cool setpoint" temperature be higher than the "heat setpoint" temperature? Hi, Easy to remember this way; cool down to, heat upto the set temp. |
Setting a programmable thermostat
Except that most people to save on energy costs will cool up and warm down.
A setting of 68-70 in winter will save on heating costs while a setting of 76-78 in summer will save on cooling cost. "Tony Hwang" wrote in message ... gcotterl wrote: Is the "cool setpoint" the temperature when the air-conditioner goes on? Is the "heat setpoint" the temperature when the heater goes on? Should the "cool setpoint" temperature be higher than the "heat setpoint" temperature? Hi, Easy to remember this way; cool down to, heat upto the set temp. |
Setting a programmable thermostat
Mark wrote:
Except that most people to save on energy costs will cool up and warm down. A setting of 68-70 in winter will save on heating costs while a setting of 76-78 in summer will save on cooling cost. "Tony Hwang" wrote in message ... gcotterl wrote: Is the "cool setpoint" the temperature when the air-conditioner goes on? Is the "heat setpoint" the temperature when the heater goes on? Should the "cool setpoint" temperature be higher than the "heat setpoint" temperature? Hi, Easy to remember this way; cool down to, heat upto the set temp. Hmmm, My power and NG cost is fixed for long term. Any way is there any one who does not know that? One reason using programmable 'stat is to save energy. I use wireless 'stat. In summer, it moves to upstairs, in winter, it relocates to downstairs. |
Setting a programmable thermostat
Hi Tony,
What do mean 'fixed for long term'? I'm locked in for a price per CCF on my gas for the next year, but the electric has yet to get the competition in our area so cost per KWH varies by month. Regardless the unit price, I still pay by how much I consume. I haven't seen a wireless stat. I'll have go Google that! My stat is located in a hallway where it isn't always indicative of the temp I want in the living space. I have to adjust regularly based on what rooms we're using and the time of day. A wireless sounds like just what I need! Mark "Tony Hwang" wrote in message ... Mark wrote: Except that most people to save on energy costs will cool up and warm down. A setting of 68-70 in winter will save on heating costs while a setting of 76-78 in summer will save on cooling cost. "Tony Hwang" wrote in message ... gcotterl wrote: Is the "cool setpoint" the temperature when the air-conditioner goes on? Is the "heat setpoint" the temperature when the heater goes on? Should the "cool setpoint" temperature be higher than the "heat setpoint" temperature? Hi, Easy to remember this way; cool down to, heat upto the set temp. Hmmm, My power and NG cost is fixed for long term. Any way is there any one who does not know that? One reason using programmable 'stat is to save energy. I use wireless 'stat. In summer, it moves to upstairs, in winter, it relocates to downstairs. |
Setting a programmable thermostat
"Mark" wrote in message ... Hi Tony, What do mean 'fixed for long term'? I'm locked in for a price per CCF on my gas for the next year, but the electric has yet to get the competition in our area so cost per KWH varies by month. Regardless the unit price, I still pay by how much I consume. I haven't seen a wireless stat. I'll have go Google that! My stat is located in a hallway where it isn't always indicative of the temp I want in the living space. I have to adjust regularly based on what rooms we're using and the time of day. A wireless sounds like just what I need! Don't worry about it...Soon you will get a wireless stat from The Obamalord and the government will decide how warm or cool your home is comrade... Mark "Tony Hwang" wrote in message ... Mark wrote: Except that most people to save on energy costs will cool up and warm down. A setting of 68-70 in winter will save on heating costs while a setting of 76-78 in summer will save on cooling cost. "Tony Hwang" wrote in message ... gcotterl wrote: Is the "cool setpoint" the temperature when the air-conditioner goes on? Is the "heat setpoint" the temperature when the heater goes on? Should the "cool setpoint" temperature be higher than the "heat setpoint" temperature? Hi, Easy to remember this way; cool down to, heat upto the set temp. Hmmm, My power and NG cost is fixed for long term. Any way is there any one who does not know that? One reason using programmable 'stat is to save energy. I use wireless 'stat. In summer, it moves to upstairs, in winter, it relocates to downstairs. |
Setting a programmable thermostat
In article ,
"benick" wrote: Don't worry about it...Soon you will get a wireless stat from The Obamalord and the government will decide how warm or cool your home is comrade... Good grief. Do you have to use *every* thread as an excuse to espouse your political views? |
Setting a programmable thermostat
Tony Hwang wrote: One reason using programmable 'stat is to save energy. That's the theory at least, however the savings are mostly based on unoccupied times, and for folks who are retired or otherwise always at home, those opportunities don't really exist. Rather similar to hybrid cars getting lousy MPG in areas with high speed roads and little stop and go traffic, the savings opportunities just don't exist. |
Setting a programmable thermostat
Smitty Two wrote: In article , "benick" wrote: Don't worry about it...Soon you will get a wireless stat from The Obamalord and the government will decide how warm or cool your home is comrade... Good grief. Do you have to use *every* thread as an excuse to espouse your political views? Kalifornia is already trying this, and has been pre-Obummer, so it's not his fault. |
Setting a programmable thermostat
Smitty Two wrote: In article , "benick" wrote: Don't worry about it...Soon you will get a wireless stat from The Obamalord and the government will decide how warm or cool your home is comrade... Good grief. Do you have to use *every* thread as an excuse to espouse your political views? Actually, there is some validity to the concept of remote control of thermostats, but not in the way that Kalifornis is trying. Control of temperature setpoints isn't needed, but for air conditioning and electric based heating (resistive or heat pump), distribution of thermostats that listened to a central time source such as GPS or WWVB and only operated heating or cooling cycles in certain 15 minute blocks set so that the overall distribution had half the thermostats operating in one block and half in the other could make a pretty significant reduction in peak electrical loads on the grid and help provide grid capacity without grid upgrades. |
Setting a programmable thermostat
Pete C. wrote:
Rather similar to hybrid cars getting lousy MPG in areas with high speed roads and little stop and go traffic, the savings opportunities just don't exist. The only hybrid I have read very detailed info on is the Prius. The EPA mileage is 48 city, 45 highway (EPA gives an idea what mileage is like). Consumer Reports *tests* had a higher highway mileage than city with 44mpg overall. (That is for the old Prius - there is a new 2010 model out - haven't seen much info except mileage is higher.) The Prius does not get "lousy" highway mileage. The Prius gets high highway mileage because: - I has a relatively small engine. You don't need high end power often and when it is needed both the gas engine and electric motors are used. The engine operates in a more efficient band. - The gas engine is a more efficient Atkinson cycle - the intake valves stay open part of the compression stroke making the compression stroke, in effect, shorter than the power stroke. More of the energy is captured on the power stroke. The engine can change the valve timing. I have not seen it explained, but I believe the engine shifts toward a conventional engine when high power is needed. A Ford Fusion hybrid coming out has the features above - haven't seen details. -- bud-- |
Setting a programmable thermostat
bud-- wrote: Pete C. wrote: Rather similar to hybrid cars getting lousy MPG in areas with high speed roads and little stop and go traffic, the savings opportunities just don't exist. The only hybrid I have read very detailed info on is the Prius. The EPA mileage is 48 city, 45 highway (EPA gives an idea what mileage is like). Consumer Reports *tests* had a higher highway mileage than city with 44mpg overall. (That is for the old Prius - there is a new 2010 model out - haven't seen much info except mileage is higher.) The Prius does not get "lousy" highway mileage. The Prius gets high highway mileage because: - I has a relatively small engine. You don't need high end power often and when it is needed both the gas engine and electric motors are used. The engine operates in a more efficient band. - The gas engine is a more efficient Atkinson cycle - the intake valves stay open part of the compression stroke making the compression stroke, in effect, shorter than the power stroke. More of the energy is captured on the power stroke. The engine can change the valve timing. I have not seen it explained, but I believe the engine shifts toward a conventional engine when high power is needed. A Ford Fusion hybrid coming out has the features above - haven't seen details. -- bud-- A hybrid vehicle can only get MPG improvements in three possible ways: 1. Energy recapture from regenerative braking 2. Electric boost with energy from a battery pack during acceleration, allowing the use of an under powered IC engine. 3. Electric boost using energy from an external source i.e. plug-in hybrid. Method 1 requires the normal driving pattern to include a fair amount of braking in order to have any measurable effect on MPG. Where I live, I drive about 300 yards on my street, then accelerate onto a 65 MPH road and my trip is pretty much no stop at 65-70 until I reach my destination, which provides virtually no regenerative braking energy recovery. Method 2 requires method 1 or 3 in order to have energy available to provide the boost. If the engine is under powered and there is not energy available in the battery to provide boost, you risk an 80,000# enema when you find you don't have the acceleration to safely merge onto the highway. Method 3 isn't really an efficiency improvement at all, it's simply a dual fuel option, you still need energy to do the job. Improvements in the IC engine efficiency are not related to or tied to a hybrid setup and can readily be applied to a conventional IC only vehicle, without the extra expense of a hybrid setup. |
Setting a programmable thermostat
bud-- wrote:
.... The only hybrid I have read very detailed info on is the Prius. The EPA mileage is 48 city, 45 highway (EPA gives an idea what mileage is like). Consumer Reports *tests* had a higher highway mileage than city with 44mpg overall. That doesn't make much (any?) sense; that "overall" is lower than either EPA... .... The Prius gets high highway mileage because: - I has a relatively small engine. ... and it's driving a toy. I just recently finished a 3000 mi round-trip excursion to/from NC which included crossing the Smoky Mtn's both ways. The 300M did 32 overall in far more comfort and more stuff in it that could have put in a Prius w/o piling it on top or pulling a trailer, either of which would really improve the mileage I'm sure. :) This is a '99 approaching 100k, not even new and sports the "touring package" which doesn't include the hemi but is geared slightly lower for more responsiveness than the stock version. What mileage driven would it take to even break even $-wise, what more come out ahead irrespective of the comfort factor??? -- |
Setting a programmable thermostat
dpb wrote: bud-- wrote: ... The only hybrid I have read very detailed info on is the Prius. The EPA mileage is 48 city, 45 highway (EPA gives an idea what mileage is like). Consumer Reports *tests* had a higher highway mileage than city with 44mpg overall. That doesn't make much (any?) sense; that "overall" is lower than either EPA... Yes, it does. The EPA MPG numbers have been far from accurate for most vehicles for a long time, and not in one particular direction either. They are of only marginal value to give you an idea of what MPG class a vehicle might fall into, and not useable to compare vehicles within the same class. ... The Prius gets high highway mileage because: - I has a relatively small engine. ... and it's driving a toy. I just recently finished a 3000 mi round-trip excursion to/from NC which included crossing the Smoky Mtn's both ways. The 300M did 32 overall in far more comfort and more stuff in it that could have put in a Prius w/o piling it on top or pulling a trailer, either of which would really improve the mileage I'm sure. :) This is a '99 approaching 100k, not even new and sports the "touring package" which doesn't include the hemi but is geared slightly lower for more responsiveness than the stock version. What mileage driven would it take to even break even $-wise, what more come out ahead irrespective of the comfort factor??? That brings up several points that the hybrid-ego folks try to igno - The hybrid vehicles they tout as wonderful (though not all hybrid vehicles) are typically tiny little glorified golf carts that while great for the limited uses of urban commuting, have little value or applicability outside an urban setting. - The cost of maintaining a second vehicle in order to have the capability to do all the tasks that a tiny hybrid isn't up to will more than eliminate any savings from the tasks that the tiny hybrid can be used for. - There are smaller conventional IC only cars that are far more capable than the tiny hybrid cars, and get nearly as good mpg as the hybrids do under the most hybrid favorable driving conditions, and do so in all driving conditions and without any of the limitations of the tiny hybrids, and in many cases can eliminate the need for a second more capable vehicle saving significant $$$. |
Setting a programmable thermostat
dpb wrote:
bud-- wrote: ... The only hybrid I have read very detailed info on is the Prius. The EPA mileage is 48 city, 45 highway (EPA gives an idea what mileage is like). Consumer Reports *tests* had a higher highway mileage than city with 44mpg overall. That doesn't make much (any?) sense; that "overall" is lower than either EPA... I agree with Pete. EPA is not noted for exactly representing reality. A couple years(?) back the EPA formula was changed to better represent reality. It also depends on what the assumptions are for what 'normal' driving is. ... The Prius gets high highway mileage because: - I has a relatively small engine. ... and it's driving a toy. It is not particularly small. A lot of cars have similar space inside (or less). My kid and his wife have a couple cars and the space is similar. It is a hatchback which increases cargo volume over a regular car. Acceleration is reasonable. I think the 2010 Prius model is a little larger (with higher gas mileage). What mileage driven would it take to even break even $-wise, what more come out ahead irrespective of the comfort factor??? Consumer Reports recently rated one of the Prius models as lowest cost to own. It was based on purchase price, resale price, cost to operate, insurance (I may have missed some factors). -- bud-- |
Setting a programmable thermostat
Pete C. wrote:
bud-- wrote: Pete C. wrote: Rather similar to hybrid cars getting lousy MPG in areas with high speed roads and little stop and go traffic, the savings opportunities just don't exist. The only hybrid I have read very detailed info on is the Prius. The EPA mileage is 48 city, 45 highway (EPA gives an idea what mileage is like). Consumer Reports *tests* had a higher highway mileage than city with 44mpg overall. (That is for the old Prius - there is a new 2010 model out - haven't seen much info except mileage is higher.) The Prius does not get "lousy" highway mileage. The Prius gets high highway mileage because: - I has a relatively small engine. You don't need high end power often and when it is needed both the gas engine and electric motors are used. The engine operates in a more efficient band. - The gas engine is a more efficient Atkinson cycle - the intake valves stay open part of the compression stroke making the compression stroke, in effect, shorter than the power stroke. More of the energy is captured on the power stroke. The engine can change the valve timing. I have not seen it explained, but I believe the engine shifts toward a conventional engine when high power is needed. A Ford Fusion hybrid coming out has the features above - haven't seen details. -- bud-- A hybrid vehicle can only get MPG improvements in three possible ways: 1. Energy recapture from regenerative braking 2. Electric boost with energy from a battery pack during acceleration, allowing the use of an under powered IC engine. 3. Electric boost using energy from an external source i.e. plug-in hybrid. Method 1 requires the normal driving pattern to include a fair amount of braking in order to have any measurable effect on MPG. Where I live, I drive about 300 yards on my street, then accelerate onto a 65 MPH road and my trip is pretty much no stop at 65-70 until I reach my destination, which provides virtually no regenerative braking energy recovery. Method 2 requires method 1 or 3 in order to have energy available to provide the boost. If the engine is under powered and there is not energy available in the battery to provide boost, you risk an 80,000# enema when you find you don't have the acceleration to safely merge onto the highway. Method 3 isn't really an efficiency improvement at all, it's simply a dual fuel option, you still need energy to do the job. Improvements in the IC engine efficiency are not related to or tied to a hybrid setup and can readily be applied to a conventional IC only vehicle, without the extra expense of a hybrid setup. You missed that the gas engine use (traction and/or generator) can be controlled to operate the engine in a more efficient point in the power curve. Efficiency *is* tied to the hybrid setup. (In addition, for the Prius, the gas engine is Atkinson cycle with variable intake valve timing.) The engine is not "underpowered". As in any design the total package is engineered to work together. There is always battery energy available for acceleration. If you are highway driving you are not usually driving on flat land. On down slopes you are regenerating. In any case you will often have 'excess' gas engine power which will be used for generation (at the same time as traction) when necessary. Your comments on not having battery power available for acceleration are simply not true. Where does anyone who has evaluated a Prius say that happens. The gas engine sets the base efficiency of the car since I think all hybrids get all their energy from the gas engine. Regeneration is critical in stop-and-go to keep the efficiency high. Some other tricks could be applied to conventional cars, like stopping the engine when not moving (like at a red light). I believe the Prius has the highest (or near the top) user satisfaction of any car in US surveys. It didn't get that by being unsafe on the highway or by being cramped. -- bud-- |
Setting a programmable thermostat
bud-- wrote: dpb wrote: bud-- wrote: ... The only hybrid I have read very detailed info on is the Prius. The EPA mileage is 48 city, 45 highway (EPA gives an idea what mileage is like). Consumer Reports *tests* had a higher highway mileage than city with 44mpg overall. That doesn't make much (any?) sense; that "overall" is lower than either EPA... I agree with Pete. EPA is not noted for exactly representing reality. A couple years(?) back the EPA formula was changed to better represent reality. It also depends on what the assumptions are for what 'normal' driving is. ... The Prius gets high highway mileage because: - I has a relatively small engine. ... and it's driving a toy. It is not particularly small. A lot of cars have similar space inside (or less). My kid and his wife have a couple cars and the space is similar. It is a hatchback which increases cargo volume over a regular car. Acceleration is reasonable. I think the 2010 Prius model is a little larger (with higher gas mileage). What mileage driven would it take to even break even $-wise, what more come out ahead irrespective of the comfort factor??? Consumer Reports recently rated one of the Prius models as lowest cost to own. It was based on purchase price, resale price, cost to operate, insurance (I may have missed some factors). That bit about resale price is where most all of these attempts to calculate a TCO for these vehicles fall flat. I have never resold a vehicle, I operate them and maintain them for a long service life. The TCO claims for the hybrids may be reasonable for people who replace their vehicles every few years, but they do not represent an accurate TCO for those of us who expect 10 years or better service life from a vehicle. |
Setting a programmable thermostat
bud-- wrote: Pete C. wrote: bud-- wrote: Pete C. wrote: Rather similar to hybrid cars getting lousy MPG in areas with high speed roads and little stop and go traffic, the savings opportunities just don't exist. The only hybrid I have read very detailed info on is the Prius. The EPA mileage is 48 city, 45 highway (EPA gives an idea what mileage is like). Consumer Reports *tests* had a higher highway mileage than city with 44mpg overall. (That is for the old Prius - there is a new 2010 model out - haven't seen much info except mileage is higher.) The Prius does not get "lousy" highway mileage. The Prius gets high highway mileage because: - I has a relatively small engine. You don't need high end power often and when it is needed both the gas engine and electric motors are used. The engine operates in a more efficient band. - The gas engine is a more efficient Atkinson cycle - the intake valves stay open part of the compression stroke making the compression stroke, in effect, shorter than the power stroke. More of the energy is captured on the power stroke. The engine can change the valve timing. I have not seen it explained, but I believe the engine shifts toward a conventional engine when high power is needed. A Ford Fusion hybrid coming out has the features above - haven't seen details. -- bud-- A hybrid vehicle can only get MPG improvements in three possible ways: 1. Energy recapture from regenerative braking 2. Electric boost with energy from a battery pack during acceleration, allowing the use of an under powered IC engine. 3. Electric boost using energy from an external source i.e. plug-in hybrid. Method 1 requires the normal driving pattern to include a fair amount of braking in order to have any measurable effect on MPG. Where I live, I drive about 300 yards on my street, then accelerate onto a 65 MPH road and my trip is pretty much no stop at 65-70 until I reach my destination, which provides virtually no regenerative braking energy recovery. Method 2 requires method 1 or 3 in order to have energy available to provide the boost. If the engine is under powered and there is not energy available in the battery to provide boost, you risk an 80,000# enema when you find you don't have the acceleration to safely merge onto the highway. Method 3 isn't really an efficiency improvement at all, it's simply a dual fuel option, you still need energy to do the job. Improvements in the IC engine efficiency are not related to or tied to a hybrid setup and can readily be applied to a conventional IC only vehicle, without the extra expense of a hybrid setup. You missed that the gas engine use (traction and/or generator) can be controlled to operate the engine in a more efficient point in the power curve. Efficiency *is* tied to the hybrid setup. (In addition, for the Prius, the gas engine is Atkinson cycle with variable intake valve timing.) The engine is not "underpowered". As in any design the total package is engineered to work together. There is always battery energy available for acceleration. If you are highway driving you are not usually driving on flat land. You haven't spent much time driving in the Dallas area, have you. Flat within a few degrees of slope on 70 MPH highways for 100 miles or better. On down slopes you are regenerating. In any case you will often have 'excess' gas engine power which will be used for generation (at the same time as traction) when necessary. Your comments on not having battery power available for acceleration are simply not true. Where does anyone who has evaluated a Prius say that happens. I'm sorry to say that I have not evaluated a Prius or other small car since they would not meet more than 5% of my total vehicle needs, so they wouldn't be economical for me even if they got 200 MPG. I have friends who have hybrids in urban environments and they perform well there. All the data I have seen indicated that a hybrid will provide no advantage over a cheaper conventional car in the same high MPG small car class when operated outside an urban environment. The gas engine sets the base efficiency of the car since I think all hybrids get all their energy from the gas engine. Regeneration is critical in stop-and-go to keep the efficiency high. Some other tricks could be applied to conventional cars, like stopping the engine when not moving (like at a red light). Unless it's a plug-in hybrid, all the energy does indeed have to ultimately come from the IC engine, either directly or indirectly. I believe the Prius has the highest (or near the top) user satisfaction of any car in US surveys. It didn't get that by being unsafe on the highway or by being cramped. Probably true for those who buy Priuses. I have some friends who are pretty "green" who rented a Prius once on vacation and traded it for a conventional car the next day because they hated it. Presuming people considering buying a Prius test drive one before they buy, that would tend to eliminate those who don't like them from the potential pool of dissatisfied Prius owners, so those user satisfaction numbers probably don't mean much. |
Setting a programmable thermostat
Boy did you guys get off-topic!
Back to the OP's question on set-back thermostats - My parents, both retired, had one and used it much the same way my wife and I use ours, even though they were home during the day while we use ours while we are at work. They set it cooler at night when in bed, warm things up just before they get up so it is comfortable while they are getting dressed, and sitting around reading the paper and eating breakfast. They set it back during the middle of the day when they are more active, and then warm it back up some in the evening while eating dinner and watching TV. Seems reasonable that it is working in much the same why ours is when we aren't home. "Pete C." wrote in message ster.com... Tony Hwang wrote: One reason using programmable 'stat is to save energy. That's the theory at least, however the savings are mostly based on unoccupied times, and for folks who are retired or otherwise always at home, those opportunities don't really exist. Rather similar to hybrid cars getting lousy MPG in areas with high speed roads and little stop and go traffic, the savings opportunities just don't exist. |
Setting a programmable thermostat
Mark wrote:
Hi Tony, What do mean 'fixed for long term'? I'm locked in for a price per CCF on my gas for the next year, but the electric has yet to get the competition in our area so cost per KWH varies by month. Regardless the unit price, I still pay by how much I consume. I haven't seen a wireless stat. I'll have go Google that! My stat is located in a hallway where it isn't always indicative of the temp I want in the living space. I have to adjust regularly based on what rooms we're using and the time of day. A wireless sounds like just what I need! Mark "Tony Hwang" wrote in message ... Mark wrote: Except that most people to save on energy costs will cool up and warm down. A setting of 68-70 in winter will save on heating costs while a setting of 76-78 in summer will save on cooling cost. "Tony Hwang" wrote in message ... gcotterl wrote: Is the "cool setpoint" the temperature when the air-conditioner goes on? Is the "heat setpoint" the temperature when the heater goes on? Should the "cool setpoint" temperature be higher than the "heat setpoint" temperature? Hi, Easy to remember this way; cool down to, heat upto the set temp. Hmmm, My power and NG cost is fixed for long term. Any way is there any one who does not know that? One reason using programmable 'stat is to save energy. I use wireless 'stat. In summer, it moves to upstairs, in winter, it relocates to downstairs. Hi. My KWh and Gigiajoule rate won't change next 5 years. |
Setting a programmable thermostat
Smitty Two wrote:
In article , "benick" wrote: Don't worry about it...Soon you will get a wireless stat from The Obamalord and the government will decide how warm or cool your home is comrade... Good grief. Do you have to use *every* thread as an excuse to espouse your political views? Hmmm, Guy like him is usually yellow. |
Setting a programmable thermostat
"Tony Hwang" wrote in message ... Smitty Two wrote: In article , "benick" wrote: Don't worry about it...Soon you will get a wireless stat from The Obamalord and the government will decide how warm or cool your home is comrade... Good grief. Do you have to use *every* thread as an excuse to espouse your political views? Hmmm, Guy like him is usually yellow. Gesh , you can't even type..."Guy like you is usually yellow"...You sound like a 2nd grader...LOL...Name calling ?? That's mature..Picking on Obambam get you fighting mad does it...LOL...I guess you didn't see the story about "smart kitchens " and energy audits of homes and what they are already doing in Cali. Just keep your head in the sand..Now you can call me another name now...LOL...Gesh.... |
Setting a programmable thermostat
Pete C. wrote:
bud-- wrote: Pete C. wrote: bud-- wrote: Pete C. wrote: Rather similar to hybrid cars getting lousy MPG in areas with high speed roads and little stop and go traffic, the savings opportunities just don't exist. The only hybrid I have read very detailed info on is the Prius. The EPA mileage is 48 city, 45 highway (EPA gives an idea what mileage is like). Consumer Reports *tests* had a higher highway mileage than city with 44mpg overall. (That is for the old Prius - there is a new 2010 model out - haven't seen much info except mileage is higher.) The Prius does not get "lousy" highway mileage. The Prius gets high highway mileage because: - I has a relatively small engine. You don't need high end power often and when it is needed both the gas engine and electric motors are used. The engine operates in a more efficient band. - The gas engine is a more efficient Atkinson cycle - the intake valves stay open part of the compression stroke making the compression stroke, in effect, shorter than the power stroke. More of the energy is captured on the power stroke. The engine can change the valve timing. I have not seen it explained, but I believe the engine shifts toward a conventional engine when high power is needed. A Ford Fusion hybrid coming out has the features above - haven't seen details. -- bud-- A hybrid vehicle can only get MPG improvements in three possible ways: 1. Energy recapture from regenerative braking 2. Electric boost with energy from a battery pack during acceleration, allowing the use of an under powered IC engine. 3. Electric boost using energy from an external source i.e. plug-in hybrid. Method 1 requires the normal driving pattern to include a fair amount of braking in order to have any measurable effect on MPG. Where I live, I drive about 300 yards on my street, then accelerate onto a 65 MPH road and my trip is pretty much no stop at 65-70 until I reach my destination, which provides virtually no regenerative braking energy recovery. Method 2 requires method 1 or 3 in order to have energy available to provide the boost. If the engine is under powered and there is not energy available in the battery to provide boost, you risk an 80,000# enema when you find you don't have the acceleration to safely merge onto the highway. Method 3 isn't really an efficiency improvement at all, it's simply a dual fuel option, you still need energy to do the job. Improvements in the IC engine efficiency are not related to or tied to a hybrid setup and can readily be applied to a conventional IC only vehicle, without the extra expense of a hybrid setup. You missed that the gas engine use (traction and/or generator) can be controlled to operate the engine in a more efficient point in the power curve. Efficiency *is* tied to the hybrid setup. (In addition, for the Prius, the gas engine is Atkinson cycle with variable intake valve timing.) The engine is not "underpowered". As in any design the total package is engineered to work together. There is always battery energy available for acceleration. If you are highway driving you are not usually driving on flat land. You haven't spent much time driving in the Dallas area, have you. Flat within a few degrees of slope on 70 MPH highways for 100 miles or better. It doesn't matter. The Prius is in the 40's for highway mileage. It is also "recommended" by Consumer Reports. That is not based on hybrid, but handling, reliability, safety, .... On down slopes you are regenerating. In any case you will often have 'excess' gas engine power which will be used for generation (at the same time as traction) when necessary. Your comments on not having battery power available for acceleration are simply not true. Where does anyone who has evaluated a Prius say that happens. I'm sorry to say that I have not evaluated a Prius or other small car since they would not meet more than 5% of my total vehicle needs, so they wouldn't be economical for me even if they got 200 MPG. I have friends who have hybrids in urban environments and they perform well there. All the data I have seen indicated that a hybrid will provide no advantage over a cheaper conventional car in the same high MPG small car class when operated outside an urban environment. Hybrids use smaller engines which can get higher base MPGs. You can't do that with a conventional car because they do not have an electric motor for power boost when needed. The Prius has a higher efficiency Atkinson cycle engine with variable valve timing. You could maybe do that in a conventional car. The bottom line is the highway MPG. A Prius is in the 40's. (EPA 45 highway, I think the 2010 model is 49 highway.) I believe a well designed hybrid will always have higher MPG than an equivalent well designed conventional car. But different people can certainly need different vehicles. I am certainly not arguing you should drive a hybrid. CR had an article on savings when gas was $4.00/gal. I was surprised a Chev Tahoe Hybrid paid for the higher vehicle cost in a year and was about $4,000 cheaper than the equivalent over 5 years. (That is all I know about a Tahoe.) (The payback and savings were only about 25% due to gas mileage.) -- bud-- |
Setting a programmable thermostat
bud-- wrote: Pete C. wrote: bud-- wrote: Pete C. wrote: bud-- wrote: Pete C. wrote: Rather similar to hybrid cars getting lousy MPG in areas with high speed roads and little stop and go traffic, the savings opportunities just don't exist. The only hybrid I have read very detailed info on is the Prius. The EPA mileage is 48 city, 45 highway (EPA gives an idea what mileage is like). Consumer Reports *tests* had a higher highway mileage than city with 44mpg overall. (That is for the old Prius - there is a new 2010 model out - haven't seen much info except mileage is higher.) The Prius does not get "lousy" highway mileage. The Prius gets high highway mileage because: - I has a relatively small engine. You don't need high end power often and when it is needed both the gas engine and electric motors are used. The engine operates in a more efficient band. - The gas engine is a more efficient Atkinson cycle - the intake valves stay open part of the compression stroke making the compression stroke, in effect, shorter than the power stroke. More of the energy is captured on the power stroke. The engine can change the valve timing. I have not seen it explained, but I believe the engine shifts toward a conventional engine when high power is needed. A Ford Fusion hybrid coming out has the features above - haven't seen details. -- bud-- A hybrid vehicle can only get MPG improvements in three possible ways: 1. Energy recapture from regenerative braking 2. Electric boost with energy from a battery pack during acceleration, allowing the use of an under powered IC engine. 3. Electric boost using energy from an external source i.e. plug-in hybrid. Method 1 requires the normal driving pattern to include a fair amount of braking in order to have any measurable effect on MPG. Where I live, I drive about 300 yards on my street, then accelerate onto a 65 MPH road and my trip is pretty much no stop at 65-70 until I reach my destination, which provides virtually no regenerative braking energy recovery. Method 2 requires method 1 or 3 in order to have energy available to provide the boost. If the engine is under powered and there is not energy available in the battery to provide boost, you risk an 80,000# enema when you find you don't have the acceleration to safely merge onto the highway. Method 3 isn't really an efficiency improvement at all, it's simply a dual fuel option, you still need energy to do the job. Improvements in the IC engine efficiency are not related to or tied to a hybrid setup and can readily be applied to a conventional IC only vehicle, without the extra expense of a hybrid setup. You missed that the gas engine use (traction and/or generator) can be controlled to operate the engine in a more efficient point in the power curve. Efficiency *is* tied to the hybrid setup. (In addition, for the Prius, the gas engine is Atkinson cycle with variable intake valve timing.) The engine is not "underpowered". As in any design the total package is engineered to work together. There is always battery energy available for acceleration. If you are highway driving you are not usually driving on flat land. You haven't spent much time driving in the Dallas area, have you. Flat within a few degrees of slope on 70 MPH highways for 100 miles or better. It doesn't matter. The Prius is in the 40's for highway mileage. It is also "recommended" by Consumer Reports. That is not based on hybrid, but handling, reliability, safety, .... On down slopes you are regenerating. In any case you will often have 'excess' gas engine power which will be used for generation (at the same time as traction) when necessary. Your comments on not having battery power available for acceleration are simply not true. Where does anyone who has evaluated a Prius say that happens. I'm sorry to say that I have not evaluated a Prius or other small car since they would not meet more than 5% of my total vehicle needs, so they wouldn't be economical for me even if they got 200 MPG. I have friends who have hybrids in urban environments and they perform well there. All the data I have seen indicated that a hybrid will provide no advantage over a cheaper conventional car in the same high MPG small car class when operated outside an urban environment. Hybrids use smaller engines which can get higher base MPGs. You can't do that with a conventional car because they do not have an electric motor for power boost when needed. The Prius has a higher efficiency Atkinson cycle engine with variable valve timing. You could maybe do that in a conventional car. The bottom line is the highway MPG. A Prius is in the 40's. (EPA 45 highway, I think the 2010 model is 49 highway.) I believe a well designed hybrid will always have higher MPG than an equivalent well designed conventional car. But different people can certainly need different vehicles. I am certainly not arguing you should drive a hybrid. CR had an article on savings when gas was $4.00/gal. I was surprised a Chev Tahoe Hybrid paid for the higher vehicle cost in a year and was about $4,000 cheaper than the equivalent over 5 years. (That is all I know about a Tahoe.) (The payback and savings were only about 25% due to gas mileage.) -- bud-- The new hybrid MDTs are interesting. In the frequent stop and go applications they are typically used for the hybrid setup should be able to get a lot of benefit. On the higher MPG conventional engine, the various variable displacement techniques will provide the most benefit. The early designs sucked and were unreliable, but newer ones are a lot better. I believe there are also some CVT trans designs in the pipline that can handle a lot more power than earlier designs and they will help a lot as well. |
| All times are GMT +1. The time now is 11:59 PM. |
Powered by vBulletin® Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
Copyright ©2004 - 2014 DIYbanter