Post by thread:[OT]: Honda enters small cogeneration plant market

Looks like a very nice unit. If you have to heat with NG or Propane you might as well generate some electricity at the same time huh? If you need to made your own heat and electricity, both, this this is ideal. But is it not true that you would get less heat from the same amount of gas since some of the energy in the gas is now being made into electricity? And isn't the local power company better able to generate electricity? So if you have electric power from the grid, this is only useful as a backup generator right? I guess I would need a spreadsheet that shows operating cost and heat and electricity output vs. the same output from a standard gas heater and the local utility company. --- James. > {Original Message removed}

> I guess I would need a spreadsheet that shows operating cost and heat and > electricity output vs. the same output from a standard gas heater and the > local utility company. Or some quick math... Power generation efficiency is 20%. Is one BTU/joule/kwh/insert-your- favorite-flavor-of-energy-unit-here of electricity more or less expensive than 5 BTUs of natural gas? Natural gas is usually measured in therms... 1 therm = 100,000 BTU = 29.3 kwh Google says... www.apta.com/research/info/online/documents/fuelsurvy.pdf Outdated, for 1999-2000, but since both prices are for that time frame, something like apples and apples... $.071/kwh for electricity, $.6989/therm for natural gas = $.024/kwh 20% of the natural gas energy going into the device becomes electricity, and if I'm reading it right, 65% of the remainder is turned into home heat. So, 1 kwh of delivered electricity costs 12 cents (requiring 5 kwh of gas), but of the remaining 4 kwh of energy, 2.6 kwh go into your house as heat. Subtract that 2.6 kwh = 6.24 cents from the 12 cents, since you would pay it for home heating anyway, and you are left with 5.76 cents per kwh. If you max the sucker out, pulling its full 1 kw all the time, you stand to save about $9.65 a month. During the winter, when your furnace is on and this contraption can take up some of the slack of heating the house. If it's 65% of overall is captured as heat, then subtract 3.25 kwh = 7.8 cents from the 12 cents, leaving 4.2 cents per kwh of electricity and bringing the savings to $20.88 per month. More promising. IF it's fairly cheap, there may be a market in placing several of these at different spots throughout a largish house, replacing one large, expensive furnace with several small, cheap ones, which also offset their cost by putting some power back into the house. During the summer, of course, you'd either need to put it outside or run an additional air conditioner to offset its heat output. Mike H.

... and you would need a sound-proof room to contain the noise it makes. Not sure about the rest of you, but my AC unit *outside* is really loud, and this is supposed to be "on par" with that. It would be challenging to contain the noise in the basement, let alone with having usits spread around the house. Rolf Mike Hord wrote: {Quote hidden}>>I guess I would need a spreadsheet that shows operating cost and heat and >>electricity output vs. the same output from a standard gas heater and the >>local utility company. >> >> > >Or some quick math... > >Power generation efficiency is 20%. Is one BTU/joule/kwh/insert-your- >favorite-flavor-of-energy-unit-here of electricity more or less expensive >than 5 BTUs of natural gas? Natural gas is usually measured in therms... >1 therm = 100,000 BTU = 29.3 kwh >Google says... >www.apta.com/research/info/online/documents/fuelsurvy.pdf >Outdated, for 1999-2000, but since both prices are for that time frame, >something like apples and apples... >$.071/kwh for electricity, >$.6989/therm for natural gas = $.024/kwh >20% of the natural gas energy going into the device becomes electricity, >and if I'm reading it right, 65% of the remainder is turned into home heat. >So, 1 kwh of delivered electricity costs 12 cents (requiring 5 kwh of gas), >but of the remaining 4 kwh of energy, 2.6 kwh go into your house as >heat. Subtract that 2.6 kwh = 6.24 cents from the 12 cents, since you >would pay it for home heating anyway, and you are left with 5.76 cents >per kwh. If you max the sucker out, pulling its full 1 kw all the time, you >stand to save about $9.65 a month. During the winter, when your furnace >is on and this contraption can take up some of the slack of heating the >house. > >If it's 65% of overall is captured as heat, then subtract 3.25 kwh = >7.8 cents from the 12 cents, leaving 4.2 cents per kwh of electricity >and bringing the savings to $20.88 per month. More promising. > >IF it's fairly cheap, there may be a market in placing several of these >at different spots throughout a largish house, replacing one large, >expensive furnace with several small, cheap ones, which also offset >their cost by putting some power back into the house. > >During the summer, of course, you'd either need to put it outside or run >an additional air conditioner to offset its heat output. > >Mike H. > > >

On Tue, Nov 01, 2005 at 04:06:32PM -0600, Mike Hord wrote: > > I guess I would need a spreadsheet that shows operating cost and heat and > > electricity output vs. the same output from a standard gas heater and the > > local utility company. > > Or some quick math... > > Power generation efficiency is 20%. Is one BTU/joule/kwh/insert-your- > favorite-flavor-of-energy-unit-here of electricity more or less expensive > than 5 BTUs of natural gas? Natural gas is usually measured in therms... > 1 therm = 100,000 BTU = 29.3 kwh But you have to multiply that by an efficiency factor. From a heating perspective Electricity is 100% efficient. NG in a high efficiency unit is about 85%. > Google says... > www.apta.com/research/info/online/documents/fuelsurvy.pdf > Outdated, for 1999-2000, but since both prices are for that time frame, > something like apples and apples... > $.071/kwh for electricity, > $.6989/therm for natural gas = $.024/kwh It's apples and gorillas now. I just switched to a Time of Use plan for electricity and just locked in my NG rate for the next year. Try these on for size: Electricity: $0.0517/khw NG: $1.679/therm Ouch! That's why I'm working desparately to switch out my ancient NG furnace for electricity. BAJ

> Electricity: $0.0517/khw > NG: $1.679/therm > > Ouch! > > That's why I'm working desparately to switch out my ancient NG > furnace for > electricity. In the UK natural gas is artificially cheap due to the need to waste North Sea Gas and use it up before it should be used so consumer NG cogen plants are attractive there - which is why the Whispergen Stirling sale was made. The US pricing seems equally wrong but in the other direction. In NZ domestic electricity is almost to $NZ0.20/kWh (about $US0.14/kWh) and home cogen using old diesel engines is starting to look attractive. A single lunger Lister or similar (which will run for about forever due to low energy density) and a surplus alternator should compete very nicely with the latest rates. Diesel is about $NZ1/litre retail at present. RM

> But you have to multiply that by an efficiency factor. Only if you're using the electricity generated here for heating. {Quote hidden}> > Google says... > > www.apta.com/research/info/online/documents/fuelsurvy.pdf > > Outdated, for 1999-2000, but since both prices are for that time frame, > > something like apples and apples... > > $.071/kwh for electricity, > > $.6989/therm for natural gas = $.024/kwh > > It's apples and gorillas now. I just switched to a Time of Use plan for > electricity and just locked in my NG rate for the next year. Try these on > for size: > > Electricity: $0.0517/khw > NG: $1.679/therm > > Ouch! > > That's why I'm working desparately to switch out my ancient NG furnace for > electricity. That's brutal. Where are you? Now that I've done the math on this, I'm thinking I might start looking into a couple of electric space heaters. I have a 30 year old trailer home, and the furnace runs non-stop for several hours a day during the worst parts of winter. If I could just let it get cool in the house, and then use an electric heater to warm up in the evening, that might be better. My pets might not like it, but they all have lovely fur coats on. ;-) Mike H.

On Tue, 1 Nov 2005, Mike Hord wrote: > IF it's fairly cheap, there may be a market in placing several of these > at different spots throughout a largish house, replacing one large, > expensive furnace with several small, cheap ones, which also offset > their cost by putting some power back into the house. You do *not* put it inside. It has water pipes in and out to a remote radiator. The box has a very high grade of insulation (double they say). You can think of it as an outdoor a/c unit that just so happens to make electricity. 3.5kW is about what's required to keep a room or two warm enough to live in in the temperate zone. It would be interesting to know if the device lowers its heat output if the electrical load decreases. And if it does not, then how does it re-convert the electrical output into heat (thoughts of simple immersion heater built in). > During the summer, of course, you'd either need to put it outside or run > an additional air conditioner to offset its heat output. Good point. Peter

Not to compare the Lister with a 2 stroke petrol engine - but have you seen any comments on the $99 2stroke genset that supercheap autos are advertising? Only 350VA IIRC but even so $NZ99 seems very cheap. RP On 03/11/05, Russell McMahon <.....apptechKILLspam@spam@paradise.net.nz> wrote: {Quote hidden}> > Electricity: $0.0517/khw > > NG: $1.679/therm > > > > Ouch! > > > > That's why I'm working desparately to switch out my ancient NG > > furnace for > > electricity. > > In the UK natural gas is artificially cheap due to the need to waste > North Sea Gas and use it up before it should be used so consumer NG > cogen plants are attractive there - which is why the Whispergen > Stirling sale was made. > > The US pricing seems equally wrong but in the other direction. > > In NZ domestic electricity is almost to $NZ0.20/kWh (about > $US0.14/kWh) and home cogen using old diesel engines is starting to > look attractive. A single lunger Lister or similar (which will run for > about forever due to low energy density) and a surplus alternator > should compete very nicely with the latest rates. Diesel is about > $NZ1/litre retail at present. > > > RM > > > -

On Wed, 2005-11-02 at 12:31 -0700, Bob Axtell wrote: > Peter wrote: > > > On Wed, 2 Nov 2005, Byron A Jeff wrote: > > > >> Electricity: $0.0517/khw > >> NG: $1.679/therm > > > > > > How come your power is so cheap ? Is this a regional thing ? > > > > Peter > > Wow! I pay $.11/kwh. where do you live, Byron? I don't know about Byron, but in Ontario, Canada the rates for electricity are (all in CND$ of course): $0.050/kWh (first 750kWh) $0.058/kWh thereafter Last year it was $0.043 and $0.047, but that rate couldn't last forever Natural gas is $0.35325/cubic meter, I don't know how that converts to "therm". TTYL ----------------------------- Herbert's PIC Stuff: http://repatch.dyndns.org:8383/pic_stuff/

According to http://www.spe.org/spe/jsp/basic/0,,1104_1732,00.html 1 cubic foot of natural gas is 1025 BTU, and 1 Therm is 100,000 BTU. Then, thanks to the Google Calculator, we wind up with 1 cubic metre = 0.361975334 therm. On 11/2/05, Herbert Graf <EraseMEmailinglist2spam_OUTTakeThisOuTfarcite.net> wrote: {Quote hidden}> On Wed, 2005-11-02 at 12:31 -0700, Bob Axtell wrote: > > Peter wrote: > > > > > On Wed, 2 Nov 2005, Byron A Jeff wrote: > > > > > >> Electricity: $0.0517/khw > > >> NG: $1.679/therm > > > > > > > > > How come your power is so cheap ? Is this a regional thing ? > > > > > > Peter > > > > Wow! I pay $.11/kwh. where do you live, Byron? > > I don't know about Byron, but in Ontario, Canada the rates for > electricity are (all in CND$ of course): > > $0.050/kWh (first 750kWh) > $0.058/kWh thereafter > > Last year it was $0.043 and $0.047, but that rate couldn't last forever > > Natural gas is $0.35325/cubic meter, I don't know how that converts to > "therm". > > TTYL > > > ----------------------------- > Herbert's PIC Stuff: > http://repatch.dyndns.org:8383/pic_stuff/ > > -

I've got a few extension cords, and I'm only in Michigan. Mind if I buy some electricity from you? Alternately we could start up Tesla's experiments again. (pun intended:) Here we get (I believe) $0.09 for the first 500 or so kWH, then $0.11 thereafter. Your $0.050[CAD] translates to $0.042[USD], which is less that half what I'm paying. Are your utilities regulated? We went through deregulation several years ago... -Adam On 11/2/05, Herbert Graf <mailinglist2spam_OUTfarcite.net> wrote: {Quote hidden}> On Wed, 2005-11-02 at 12:31 -0700, Bob Axtell wrote: > > Peter wrote: > > > > > On Wed, 2 Nov 2005, Byron A Jeff wrote: > > > > > >> Electricity: $0.0517/khw > > >> NG: $1.679/therm > > > > > > > > > How come your power is so cheap ? Is this a regional thing ? > > > > > > Peter > > > > Wow! I pay $.11/kwh. where do you live, Byron? > > I don't know about Byron, but in Ontario, Canada the rates for > electricity are (all in CND$ of course): > > $0.050/kWh (first 750kWh) > $0.058/kWh thereafter > > Last year it was $0.043 and $0.047, but that rate couldn't last forever > > Natural gas is $0.35325/cubic meter, I don't know how that converts to > "therm". > > TTYL > > > ----------------------------- > Herbert's PIC Stuff: > http://repatch.dyndns.org:8383/pic_stuff/ > > -

According to www.eia.doe.gov/cneaf/electricity/epm/table5_6_a.html Michigan is slightly below average. Kentucky has 6.5 cents per kWH, while New York is at 15 cents per kWH. It would be interesting to peg the cost of electricity against the cost of living. I understand that canada's cost of living is lower than the US, but I don't know if it's significant, or by how much. This could be one reason why electricity is cheaper (pay the workers less)... Obviously it's time to outsource our power needs. We're already doing it with oil, time to do it with electricity. -Adam On 11/2/05, M. Adam Davis <@spam@stienmanKILLspamgmail.com> wrote: {Quote hidden}> I've got a few extension cords, and I'm only in Michigan. Mind if I > buy some electricity from you? Alternately we could start up Tesla's > experiments again. (pun intended:) > > Here we get (I believe) $0.09 for the first 500 or so kWH, then $0.11 > thereafter. Your $0.050[CAD] translates to $0.042[USD], which is less > that half what I'm paying. > > Are your utilities regulated? We went through deregulation several years ago... > > -Adam > > On 11/2/05, Herbert Graf <KILLspammailinglist2KILLspamfarcite.net> wrote: > > On Wed, 2005-11-02 at 12:31 -0700, Bob Axtell wrote: > > > Peter wrote: > > > > > > > On Wed, 2 Nov 2005, Byron A Jeff wrote: > > > > > > > >> Electricity: $0.0517/khw > > > >> NG: $1.679/therm > > > > > > > > > > > > How come your power is so cheap ? Is this a regional thing ? > > > > > > > > Peter > > > > > > Wow! I pay $.11/kwh. where do you live, Byron? > > > > I don't know about Byron, but in Ontario, Canada the rates for > > electricity are (all in CND$ of course): > > > > $0.050/kWh (first 750kWh) > > $0.058/kWh thereafter > > > > Last year it was $0.043 and $0.047, but that rate couldn't last forever > > > > Natural gas is $0.35325/cubic meter, I don't know how that converts to > > "therm". > > > > TTYL > > > > > > ----------------------------- > > Herbert's PIC Stuff: > > http://repatch.dyndns.org:8383/pic_stuff/ > > > > --

On Wed, 2005-11-02 at 15:31 -0500, M. Adam Davis wrote: > I've got a few extension cords, and I'm only in Michigan. Mind if I > buy some electricity from you? Alternately we could start up Tesla's > experiments again. (pun intended:) > > Here we get (I believe) $0.09 for the first 500 or so kWH, then $0.11 > thereafter. Your $0.050[CAD] translates to $0.042[USD], which is less > that half what I'm paying. > > Are your utilities regulated? We went through deregulation several years ago... Hehe, yes, and no, it's kinda a weird situation. Basically the price we pay is regulated. However, it is adjusted so that the regulated price matches the actual average cost of power. Sometimes they average lower, sometimes they average higher. It's a complicated setup that is debated about constantly. TTYL ----------------------------- Herbert's PIC Stuff: http://repatch.dyndns.org:8383/pic_stuff/

And here's a long term bet with some links to the dept of energy. Apparantly inflation has been groing faster than the cost of electricity. Therefore electricity is cheaper now than it was last year, in adjusted 1995 dollars. The dept. of energy indicates that it will continue to fall through 2007. So I suppose I shouldn't complain. Would still be nice to have sub $0.05/kWH electricity though. Then you look a solar power. About $4 per watt for an average panel, new. Over a year you get perhaps 4000 good solar hours (10 hours a day is 3650 hours). So you are getting 4kWH per year out of a $4 investment. About 10 times the cost of electricity. After installtion and all the other equipment needed you're still looking at a 15 year payback, at which point the solar panel might be running at 80% efficiency, if it's still running at all. -Adam On 11/2/05, M. Adam Davis <RemoveMEstienmanTakeThisOuTgmail.com> wrote: {Quote hidden}> According to > www.eia.doe.gov/cneaf/electricity/epm/table5_6_a.html > Michigan is slightly below average. Kentucky has 6.5 cents per kWH, > while New York is at 15 cents per kWH. > > It would be interesting to peg the cost of electricity against the > cost of living. I understand that canada's cost of living is lower > than the US, but I don't know if it's significant, or by how much. > This could be one reason why electricity is cheaper (pay the workers > less)... > > Obviously it's time to outsource our power needs. We're already doing > it with oil, time to do it with electricity. > > -Adam > > On 11/2/05, M. Adam Davis <spamBeGonestienmanspamBeGonegmail.com> wrote: > > I've got a few extension cords, and I'm only in Michigan. Mind if I > > buy some electricity from you? Alternately we could start up Tesla's > > experiments again. (pun intended:) > > > > Here we get (I believe) $0.09 for the first 500 or so kWH, then $0.11 > > thereafter. Your $0.050[CAD] translates to $0.042[USD], which is less > > that half what I'm paying. > > > > Are your utilities regulated? We went through deregulation several years ago... > > > > -Adam > > > > On 11/2/05, Herbert Graf <TakeThisOuTmailinglist2EraseMEspam_OUTfarcite.net> wrote: > > > On Wed, 2005-11-02 at 12:31 -0700, Bob Axtell wrote: > > > > Peter wrote: > > > > > > > > > On Wed, 2 Nov 2005, Byron A Jeff wrote: > > > > > > > > > >> Electricity: $0.0517/khw > > > > >> NG: $1.679/therm > > > > > > > > > > > > > > > How come your power is so cheap ? Is this a regional thing ? > > > > > > > > > > Peter > > > > > > > > Wow! I pay $.11/kwh. where do you live, Byron? > > > > > > I don't know about Byron, but in Ontario, Canada the rates for > > > electricity are (all in CND$ of course): > > > > > > $0.050/kWh (first 750kWh) > > > $0.058/kWh thereafter > > > > > > Last year it was $0.043 and $0.047, but that rate couldn't last forever > > > > > > Natural gas is $0.35325/cubic meter, I don't know how that converts to > > > "therm". > > > > > > TTYL > > > > > > > > > ----------------------------- > > > Herbert's PIC Stuff: > > > http://repatch.dyndns.org:8383/pic_stuff/ > > > > > > -- >

I should consider linking to the bet: http://www.longbets.org/117 -Adam On 11/2/05, M. Adam Davis <RemoveMEstienmanTakeThisOuTgmail.com> wrote: {Quote hidden}> And here's a long term bet with some links to the dept of energy. > Apparantly inflation has been groing faster than the cost of > electricity. Therefore electricity is cheaper now than it was last > year, in adjusted 1995 dollars. The dept. of energy indicates that it > will continue to fall through 2007. > > So I suppose I shouldn't complain. Would still be nice to have sub > $0.05/kWH electricity though. > > Then you look a solar power. About $4 per watt for an average panel, > new. Over a year you get perhaps 4000 good solar hours (10 hours a > day is 3650 hours). So you are getting 4kWH per year out of a $4 > investment. About 10 times the cost of electricity. After > installtion and all the other equipment needed you're still looking at > a 15 year payback, at which point the solar panel might be running at > 80% efficiency, if it's still running at all. > > -Adam

Olin Lathrop wrote: > Randy Glenn wrote: > >>According to http://www.spe.org/spe/jsp/basic/0,,1104_1732,00.html 1 >>cubic foot of natural gas is 1025 BTU, and 1 Therm is 100,000 BTU. >> >>Then, thanks to the Google Calculator, we wind up with 1 cubic metre = >>0.361975334 therm. > > > This doesn't make any sense since the volume doesn't specify the mass of > methane you're buying, but the amount of energy you get from burning it is > proportional to the mass. > > > ****************************************************************** > Embed Inc, Littleton Massachusetts, (978) 742-9014. #1 PIC > consultant in 2004 program year. http://www.embedinc.com/products My reference gives around 1000 BTU/ft^3 at standard atmospheric pressure. And since natural gas is delivered at low gauge pressure that value is pretty close. On my gas bill there is always a pressure correction factor applied to the usage. Jim

> Not to compare the Lister with a 2 stroke petrol engine - but have > you > seen any comments on the $99 2 stroke genset that supercheap autos > are > advertising? > Only 350VA IIRC but even so $NZ99 seems very cheap. I purchased a 700 watt nominal petro genset recently for $NZ99 from Benchmark. They said it was their standard price (!!!). The problems with this as a competitor with mains power are: - Hours before maintenance would be low. - Petrol costs about 50% more than diesel for same energy content. Say unit would run for 1000 hours with no maintenance. It may well not last that long ! :-( $99/$1000 = $0.10/hour. Assume 750 watt electrical and 80% efficient overall and 10 kWh/litre for petrol and $1.40/l and 15% of output is electrical. All these assumptions are wrong !!!! :-) But: Output = 0.75/.15 = 5 kW (750 W elec, 4250 W heat). Energy in is 5 kW/0.8 = 5.25 kW. Fuel/hr = 5.25/10 = 0.525 l Fuel cost/hr = .525 x $1.40 =~ $0.75 If we throw unit away at 1000 hrs cost per hour is $0.85/hr = $0.17/unit That's about the cost of electricity per unit now !!!!!!!!!!!!!!! Use a Lister where we don't throw it away (but it costs $500 - $1000 to find the parts to start with) and the incremental cost is below mains electricity cost. I'm SURE the above is quite wrong in places (quite apart from possible errors) but it's given me enough food for thought to see what my genset will actually accomplish. Being able to use the heat is a major issue. Good hot water storage would help. . Being able to store electric power would be useful but battery costs get nasty. Shame that electricity component is typically so small. RM

On Wed, Nov 02, 2005 at 08:41:53AM -0600, Mike Hord wrote: {Quote hidden}> > But you have to multiply that by an efficiency factor. > > Only if you're using the electricity generated here for heating. > > > > Google says... > > > www.apta.com/research/info/online/documents/fuelsurvy.pdf > > > Outdated, for 1999-2000, but since both prices are for that time frame, > > > something like apples and apples... > > > $.071/kwh for electricity, > > > $.6989/therm for natural gas = $.024/kwh > > > > It's apples and gorillas now. I just switched to a Time of Use plan for > > electricity and just locked in my NG rate for the next year. Try these on > > for size: > > > > Electricity: $0.0517/khw > > NG: $1.679/therm > > > > Ouch! > > > > That's why I'm working desparately to switch out my ancient NG furnace for > > electricity. > > That's brutal. Where are you? Georgia, US. NG is a deregulated industry here. So we have a "free" market. Of course prices are so close between marketers that some type of collusion is going on. > Now that I've done the math on this, I'm thinking I might start looking > into a couple of electric space heaters. I have a 30 year old trailer home, > and the furnace runs non-stop for several hours a day during the worst > parts of winter. If I could just let it get cool in the house, and then use > an electric heater to warm up in the evening, that might be better. I'm thinking about buying a couple or three electric space heaters until I can get this furnace replaced. Fortunately it's been unseasonably warm so far. BAJ

On Wed, Nov 02, 2005 at 10:11:22PM +0200, Peter wrote: > > On Wed, 2 Nov 2005, Byron A Jeff wrote: > > >Electricity: $0.0517/khw > >NG: $1.679/therm > > How come your power is so cheap ? Is this a regional thing ? Three reasons. The first is that electricity is a regulated industry here. So all price changes must go through an elected public service commission. The second is that electricity in the area is generated with coal and nuclear, whose prices and production have not been affected by the hurricanes which have thrashed the Gulf coast in the last couple of months. Finally as I stated in my first post, I'm using a Time of Use rate system that prices the kwh based on the time that you use it. Off peak times, which includes all winter, are priced as above. However in peak times, which is 2-7 PM during the summer months of June/September, the price soars to $0.20/kwh! That's a problem that I have 8 months to figure out. Even during the summer it's worthwhile because the off peak price outside of the 2-7PM window is nearly $0.03/kwh cheaper than the standard rate. I have a twofold basic gameplan for dealing with peak hours. First is energy timeshifting. Simply put I'll store energy in batteries during the 19 off peak hours/day and use the battery bank during the 5 on peak hours/day. The second is that the primary peak hours load is cooling. I'm been thinking up alternative cooling strategies for peak hours. My current off the wall idea is using a freezer full of ice as a heat exchanger, along with an automotive heat core/blower combo to cool the air. So the only power requirements would be for the pumps and the fans, which can be handled (I think) by a sufficiently powerful battery bank. I can use the normal central air to cool the house during off peak, possibly even loading up a bit in the late morning/early afternoon hours, and using the alternative cooling during the peak hours with off grid power. I've also thought about using some artificial shading with greenhouse sunshade to keep the sun from beating on the house during the middle of the day. Along with the increased insulation and weatherstripping that I'm already putting in, I can get away without running the central air for 5 hours/day in the summer. It's a project that I have all winter to work on. I just need to be ready by June 1 of next year. BAJ

Russell McMahon wrote: > I purchased a 700 watt nominal petro genset recently for $NZ99 > Say unit would run for 1000 hours with no maintenance. > $99/$1000 = $0.10/hour. > Assume 750 watt electrical and 80% efficient overall and 10 kWh/litre > for petrol and $1.40/l and 15% of output is electrical. > Output = 0.75/.15 = 5 kW (750 W elec, 4250 W heat). > Energy in is 5 kW/0.8 = 5.25 kW. > Fuel/hr = 5.25/10 = 0.525 l > Fuel cost/hr = .525 x $1.40 =~ $0.75 So far I follow you... > If we throw unit away at 1000 hrs cost per hour is $0.85/hr = > $0.17/unit > > That's about the cost of electricity per unit now Russell, what is "unit" in this context? I thought it meant a unit of the generator, but then the numbers don't make sense to me. What does a cost per unit ($0.17/unit) mean? Calculating the cost of electricity according to your numbers, I get: TCO (based on 1000 h): 850 NZD Electric energy produced: 750 kWh TCO per electric energy produced: 850 NZD/750 kWh = 1.13 NZD/kWh Gerhard

Gerhard, A "unit" refers to the unit of power measurement - 1 unit = 1kw/hr. This may be an NZ / UK usage. I/m not sure where it came from but it is commonly used here. Richard P On 04/11/05, Gerhard Fiedler <listsEraseME.....connectionbrazil.com> wrote: {Quote hidden}> Russell McMahon wrote: > > > I purchased a 700 watt nominal petro genset recently for $NZ99 > > Say unit would run for 1000 hours with no maintenance. > > $99/$1000 = $0.10/hour. > > Assume 750 watt electrical and 80% efficient overall and 10 kWh/litre > > for petrol and $1.40/l and 15% of output is electrical. > > Output = 0.75/.15 = 5 kW (750 W elec, 4250 W heat). > > Energy in is 5 kW/0.8 = 5.25 kW. > > Fuel/hr = 5.25/10 = 0.525 l > > Fuel cost/hr = .525 x $1.40 =~ $0.75 > > So far I follow you... > > > If we throw unit away at 1000 hrs cost per hour is $0.85/hr = > > $0.17/unit > > > > That's about the cost of electricity per unit now > > Russell, what is "unit" in this context? I thought it meant a unit of the > generator, but then the numbers don't make sense to me. What does a cost > per unit ($0.17/unit) mean? > > Calculating the cost of electricity according to your numbers, I get: > TCO (based on 1000 h): 850 NZD > Electric energy produced: 750 kWh > TCO per electric energy produced: 850 NZD/750 kWh = 1.13 NZD/kWh > > Gerhard > > -

On Thu, 3 Nov 2005, Byron A Jeff wrote: > Off peak times, which includes all winter, are priced as above. However in peak > times, which is 2-7 PM during the summer months of June/September, the price > soars to $0.20/kwh! That's a problem that I have 8 months to figure out. Even during > the summer it's worthwhile because the off peak price outside of the 2-7PM window > is nearly $0.03/kwh cheaper than the standard rate. Ouch. Ok. > the normal central air to cool the house during off peak, possibly even loading up > a bit in the late morning/early afternoon hours, and using the alternative cooling > during the peak hours with off grid power. You could look into a brick pile heat storage device. Essentially you fill a basement room with perforated brick and arrange for it to be chilled by the a/c when off peak. At peak you run air through the brick pile which is now very cold and the a/c is shut off. This is not necessarily very hygienic however. Another trick would be to put the a/c condenser in/spray with water from your (shaded) pool. > I've also thought about using some artificial shading with greenhouse sunshade to > keep the sun from beating on the house during the middle of the day. Along with the > increased insulation and weatherstripping that I'm already putting in, I can get > away without running the central air for 5 hours/day in the summer. There are alot of resources on heat regulation using landscaping. Sunshading should work also I read that moving a tree or two can help. Peter

{Quote hidden}>> Russell McMahon wrote: >> >>> I purchased a 700 watt nominal petro genset recently for $NZ99 >>> Say unit would run for 1000 hours with no maintenance. >>> $99/$1000 = $0.10/hour. >>> Assume 750 watt electrical and 80% efficient overall and 10 kWh/litre >>> for petrol and $1.40/l and 15% of output is electrical. >>> Output = 0.75/.15 = 5 kW (750 W elec, 4250 W heat). >>> Energy in is 5 kW/0.8 = 5.25 kW. >>> Fuel/hr = 5.25/10 = 0.525 l >>> Fuel cost/hr = .525 x $1.40 =~ $0.75 >> >> So far I follow you... >> >>> If we throw unit away at 1000 hrs cost per hour is $0.85/hr = >>> $0.17/unit >>> >>> That's about the cost of electricity per unit now >> >> Russell, what is "unit" in this context? I thought it meant a unit of the >> generator, but then the numbers don't make sense to me. What does a cost >> per unit ($0.17/unit) mean? >> >> Calculating the cost of electricity according to your numbers, I get: >> TCO (based on 1000 h): 850 NZD >> Electric energy produced: 750 kWh >> TCO per electric energy produced: 850 NZD/750 kWh = 1.13 NZD/kWh Richard Prosser wrote: > A "unit" refers to the unit of power measurement - 1 unit = 1kw/hr. Oh, thanks -- I take this to be kWh (kW * h rather than kW / h, right? :) I guess then the number would be 0.17 NZD/kWh _total_ energy output -- but this can't really be compared easily to electric energy prices. Gerhard

On Thu, Nov 03, 2005 at 10:05:16PM +0200, Peter wrote: > > On Thu, 3 Nov 2005, Byron A Jeff wrote: > > >Off peak times, which includes all winter, are priced as above. However in > >peak > >times, which is 2-7 PM during the summer months of June/September, the > >price > >soars to $0.20/kwh! That's a problem that I have 8 months to figure out. > >Even during > >the summer it's worthwhile because the off peak price outside of the 2-7PM > >window > >is nearly $0.03/kwh cheaper than the standard rate. > > Ouch. Ok. Agreed. I decided the roll the dice on it though. {Quote hidden}> > >the normal central air to cool the house during off peak, possibly even > >loading up > >a bit in the late morning/early afternoon hours, and using the alternative > >cooling > >during the peak hours with off grid power. > > You could look into a brick pile heat storage device. Essentially you > fill a basement room with perforated brick and arrange for it to be > chilled by the a/c when off peak. At peak you run air through the brick > pile which is now very cold and the a/c is shut off. This is not > necessarily very hygienic however. Another trick would be to put the a/c > condenser in/spray with water from your (shaded) pool. The condenser can't be run during peak periods. I could afford to run the fan. Using the freezer full of ice is essentially the same idea. Water is a much more compact thermal load than bricks/rocks. Also liquid transfers heat better than air. {Quote hidden}> > >I've also thought about using some artificial shading with greenhouse > >sunshade to > >keep the sun from beating on the house during the middle of the day. Along > >with the > >increased insulation and weatherstripping that I'm already putting in, I > >can get > >away without running the central air for 5 hours/day in the summer. > > There are alot of resources on heat regulation using landscaping. > Sunshading should work also I read that moving a tree or two can help. Sunshade can be used with discretion. Put it up when you need it, take it down when you don't. Also sunshade doesn't drop leaves in the fall. BAJ

Byron, (This reply is late, but they say that Winter will be late this year... :-) On Thu, 3 Nov 2005 07:17:00 -0500, Byron A Jeff wrote: > On Wed, Nov 02, 2005 at 10:11:22PM +0200, Peter wrote: > > > > On Wed, 2 Nov 2005, Byron A Jeff wrote: > > > > >Electricity: $0.0517/khw > > >NG: $1.679/therm Stone me, that electricity really is cheap! Here in the UK gas is priced in kWh, so it's much easier to compare with electricity. We've just had gas and electricity price increases, but gas is still much cheaper than electricity. {Quote hidden}> > How come your power is so cheap ? Is this a regional thing ? > > Three reasons. The first is that electricity is a regulated industry here. So all > price changes must go through an elected public service commission. The second is > that electricity in the area is generated with coal and nuclear, whose prices and > production have not been affected by the hurricanes which have thrashed the Gulf > coast in the last couple of months. Finally as I stated in my first post, I'm using > a Time of Use rate system that prices the kwh based on the time that you use it. > Off peak times, which includes all winter, are priced as above. However in peak > times, which is 2-7 PM during the summer months of June/September, the price > soars to $0.20/kwh! That's a problem that I have 8 months to figure out. Even during > the summer it's worthwhile because the off peak price outside of the 2-7PM window > is nearly $0.03/kwh cheaper than the standard rate. Gas here is UK£0.0317 per kWh (US$0.551 - nearly the same as your electricity!). I have "Economy 7" electricity metering, which means that from 00:00 to 07:00 (with a bit of jitter caused by the timeswitch) I pay UK£0.0345 per kWh (US$0.0601), but for the rest of the time it's more than three times that, UK£0.1125 (US£0.196). So whereas you have 5 hours/day of "peak" pricing for 4 months of the year, we have it for 17 hours/365. However, after a certain consumption at the "peak" rate during a billing period (usually a quarter), it drops to UK£0.088 (US$0.153), so whereas yours gets more expensive if you use more, ours gets cheaper! > I have a twofold basic gameplan for dealing with peak hours. First is energy > timeshifting. Simply put I'll store energy in batteries during the 19 off peak > hours/day and use the battery bank during the 5 on peak hours/day. I did consider storing the cheap night electricity in batteries and using it from them during the day, but the arithmetic is against it, especially since the cost/life of batteries would be pretty horrendous. Your 5/19 pattern makes it much more feasible than our 17/7. >The second > is that the primary peak hours load is cooling. I'm been thinking up alternative > cooling strategies for peak hours. My current off the wall idea is using a freezer > full of ice as a heat exchanger, along with an automotive heat core/blower combo to > cool the air. So the only power requirements would be for the pumps and the fans, > which can be handled (I think) by a sufficiently powerful battery bank. I can use > the normal central air to cool the house during off peak, possibly even loading up > a bit in the late morning/early afternoon hours, and using the alternative cooling > during the peak hours with off grid power. Of course you have the advantage that peak cooling demand is also peak insolation, so solar panels would be a better match there than here, where evenings are the peak for domestic demand. Cheers, Howard Winter St.Albans, England