New home: heat pump vs natural gas

[JohnnyG]

The reason we leased our new equipment is because we're only planning to stay in the house another 2-3 years. This way, there was no big cash outlay for something we probably wouldn't get all the value back out of when we sell the house. Much better to put the money into something like new flooring.

When we sell, the new buyers can take on the $155/month payment, or they can buy-out the lease, or we can agree to buy-out the lease.

[que3jxp]

Originally Posted by RodneyHurlbert

That being said, you are still running a compressor system with a 40 amp breaker. The hydro costs are still going to be more expensive then a 2 stage gas furnace.

That may be true when speaking of which unit uses more electricity BUT, when you look at which technology uses more ENERGY, the GHP will win every day of the week and twice on Sunday.

NO and I mean NO hydrocarbon based heating technology is able to hit or exceed 100% efficinency. If they were, there would be no vent stack or chimney. GHPs are regularly capable of no less than 300%. Mine is rated at 360% heating and ~500% cooling.

In the end, you may use more electriity with a GHP than a gas or oil furnace, but the GHP WILL use less energy overall AND will be FAR lower maintenance and exceedingly more climate friendly. (Provided your electricity source is not coal or oil which fortunately in Canada, is not even 30% of our total energy source)

As some here know, I am a MASSIVE GHP supporter and for all the right reasons. They are smart, low maintenance and extremely efficient. They also act as water heater, a dehumidifier AND an air conditioner. They are simply the ultimate all-in-one HVAC equipment.

Oh, and they don't NEED wells. They use closed loop systems that can be either glycol or R148/R22 based and can be installed with either vertical columns or horizontal shallow trench installation.

[TKG26]

All the jargan aside.... IF you have a 2 homes side by side of identical construction one running a heat pump and one running a 2 stage NAT GAS furnace..................... At the end of the year when the utilities are all added up the gas unit will probably heat the house for less money.. There is almost no hydro consumption from a 2stage dc gas furnace(running at 65watts)

[que3jxp]

The jargon CANNOT be set aside.

The gas unit may not use much electricity, but the GHP uses NO gas. Fossil fuels are much more volatile, price wise, than electricity. With this, it is a far more likely outcome that the GHP equipped house will cost less.

AND!!!!!

The GHP does air contitioning AND hot water all year round. With this factored in, the GHP is all but guaranteed to best any setup with an air to air A/C unit(s) and a gas furnace.

[jccamp95]

There is also some very good information on heating / cooling on FortisBC's website. They even do a cost comparison or running electric/geo/air/NG/wood....

[que3jxp]

I guess to very quickly break down how you should look at a GHP in a new construction, here is what you have when you are done installing one:

• Heat
• Air conditioning
• Hot Water
• Dehumidification in the warm months that is far better than any standalone DH or HRV can provide.

What this means is that unless you take each of these into account, you are not making an apples to apples comparision.

Also, if you are already looking at a forced air based system, you need to discount all of the duct work and the HRV unit as you need it regardless of if you use a GHP or a gas/oil furnace.

The only BIG thing that people who are unfamiliar with GHPs need to keep in mind is that GHPs are the absolute unrivaled champion of enery efficiency. Nothing can come close. The difference is so great that a GHP is, on average, at least 50% more efficient than an air to air heat pump. The only real possible detractor for a GHP is the intial installation cost and I just don't see that as an issue when you perform a full and proper ROI.

[Hurricane]

GHPs aren't technically 300% 'efficient'. That is simply a comparison of the energy consumed from the utlity company compared to the energy (heat) output of the unit.

The reason GHPs can claim such high efficiency ratings is because conventional heating appliance generate heat using energy supplied from the utility (gas or electricity). GHPs don't generate heat. They simply move heat from one place (the ground or ground water typically) into your house.

If one was to calculate the efficiency based on the heat extracted from the ground + the enrgy used to power the GHP compared to the heat output of the GHP, the efficiency would be less than 100% (probably by a fair margin). The reason the heat extracted from the ground isn't considered is becasue this is essentially 'free' heat. Both in terms of nobody has to pay for it, and nobody is having to maintain the subsurface temperatures.

The whole concept of moving heat is why you can have an air temperature on the output of 25-26 degrees when the temperature of the transfer medium (glycol or water) at only 7 - 10 degrees. (This thoroughly confuses a lot of people).

[Wayne]

Originally Posted by que3jxp

(Provided your electricity source is not coal or oil which fortunately in Canada, is not even 30% of our total energy source)

But in many parts of the country the marginal supply of electricity comes from coal, at least it does in Ontario and Alberta (I believe in Ontario the base load comes from nukes and hydro and coal makes up the difference). Therefore if everyone switched to GHPs then wouldn't we be burning a whole lot more coal and less NG? Is that a good tradeoff?

[que3jxp]

Originally Posted by Hurricane

If one was to calculate the efficiency based on the heat extracted from the ground + the enrgy used to power the GHP compared to the heat output of the GHP, the efficiency would be less than 100% (probably by a fair margin).

I'm sorry, but that logic is like saying the sun is not there because I closed my eyes.

Unless the sun goes nova or burns out unexpectedly, or the earth freezes over right to the core, there will ALWAYS be heat available from the ground.

You know, what you said is almost like saying 2 + 2 is not 4 because I chose to stop before the + sign. The fact is that the "free" heat is still heat and the COP of the average GHP is at least 3.6 for heating and as high as 5+ for cooling. No fossil fuel system has a COP anything past 0.95

What matters at the end is that GHPs do the same job as a traditional furnace, water heater and A/C unit but all wrapped in one. You can argue the semantics of it all day and night but at the time we get our energy bills, those with the GHPs will win.

Originally Posted by Wayne

But in many parts of the country the marginal supply of electricity comes from coal, at least it does in Ontario and Alberta (I believe in Ontario the base load comes from nukes and hydro and coal makes up the difference). Therefore if everyone switched to GHPs then wouldn't we be burning a whole lot more coal and less NG? Is that a good tradeoff?

But there would not be much difference (if any) to be made up.

I know that ON and AB are addicted to NG but the actual units of energy required for a GHP equipped house is lower than anything you can do.

Think of it this way. You use an amount of energy that we will baseline as 1. An equivalent sized house that has a GHP in place of all of the traditional HVAC and water heating equipment will only use ~0.5. So on a per square foot basis, if all of the houses are using only 50% as much energy, then where is the issue?

If one is concerned with coal power plants, then as the residential usage of NG goes down, divert the unused gas to NG power generators.

You see, there is one undenyable benefit to GHPs. They run off electricity that can be made in many ways. If there is a super cheap way to produce electricity, well, you immediately benefit. If there is a super clean way to make electricity, you benefit right away. All of the fossil fuel based systems are stuck on fossil fuel no matter what happens in the electricity market.

[Hurricane]

Originally Posted by que3jxp

You know, what you said is almost like saying 2 + 2 is not 4 because I chose to stop before the + sign. The fact is that the "free" heat is still heat and the COP of the average GHP is at least 3.6 for heating and as high as 5+ for cooling. No fossil fuel system has a COP anything past 0.95

I'm not sure my post was completely clear because you're argueing the same point I am. Nothing can technically be > 100% efficient without violating the law of conservation of energy. I'm simply pointing out that with GHP's the efficiency is calculated more on how much utlity energy is used to move the heat rather than how much utlity energy is used to generate the heat.

I wasn't trying to insinuate that GHP manufacturers are somehow trying to deceive consumers with sneaky calculations or anything like that.

[TKG26]

http://www.fortisbc.com/downloads/en...une%202007.pdf

I think i just answered my own questions!! WOW i am impressed! Thanfully my career as a gas fitter is not in jepardy though..... I dont think to many new construction townhomes are being built with GHP!

[que3jxp]

Originally Posted by Hurricane

I'm not sure my post was completely clear because you're argueing the same point I am.

I see where you are going with that now. Sorry.

BUT!!!

To the untrained or unknowledged individual, it could be misunderstood in the same way that I did. I guess that is what got me going on such a long babble-fest.

The core technology of any HP is the same (Be it a refridgerator or a in-window a/c unit). So given that, there other efficiency levels to discuss, but the GHP or air HP or oil furnace is a total system and cannot be reduced to subcomponents. The home owner sees a actual quanitfiable COP for any given system they choose. Where the heat comes from is for academic discussion.

TKG26

You ready to have your mind REALLY blown? There is research and development that have prototype units that are capable of as much as 800% for heating. Given that the best available right now are only in the low 400%, it will be a while before we see the crazy models. But if I can simply swap in a new one without having to replace my DX lines I have now!!! I will be there with bells on!

Off topic, the biggest issue in any HP is the compressor. I have heard of acoustic compressors (No moving parts) has anyone heard if they are close to mass marketing?

[Monobloc]

Those Fortis links are rather interesting. Looks like electric vs natural gas hot water heating are closer than people think they are. One thing that caught my eye was the wood stove vs ground source heat pump. They mention catalytic stoves being 75% efficient. My dad has an 82% efficient catalytic wood stove. I know percentage wise it's not going to compare to a GHP. But for dollars per year, it's close.

I've watched that thing in action during the winter and let me tell you, this isn't your traditional wood stove. You can touch the chimney. You walk outside and smell absolutely nothing. All you see coming out of the chimney is water vapour (early burn cycle) or nothing (later burn cycle). Natural convection and heatsink powered fan circulate the air.

[que3jxp]

Originally Posted by Monobloc

I've watched that thing in action during the winter and let me tell you, this isn't your traditional wood stove.

That is not, by chance, a GARN unit is it?

[Monobloc]

It's a Blaze King.
http://www.blazeking.com/king1107.htm

1.76 grams of emissions, uses about 1/3 the wood that his old stove used. I asked him how much creosote he got out of chimney. He said about a tablespoon every 3 years. In other words, nothing.

Cost him $4,000 but I could easily see purchasing one myself. Unfortunately my home isn't really set up to really benefit a wood stove (room design). I find the catalytic option along with the thermostat gives a nice even heat output. Not the up and down cycle that his old stove used to do.

http://www.blazeking.com/BlazeKingPosters.pdf (pictures of the features)
He didn't get the optional electric fans. (Noise, takes heat out of the firebox thus decreasing efficiency). Instead he just bought an Eco-fan. The kind that sit on top of the wood stove. Once the heatsink gets hot, the fans starts spinning. The hotter it gets, the faster it spins. Silent, free, good efficiency.
Once the thermometer gets in the "active" zone (the bigger area in the pic) you close the bypass handle and all the smoke goes through the catalyst. You can see the catalyst glowing red after awhile. That catalyst makes the wood stay hotter for longer. Oddly enough you don't get the big flames that traditional wood stoves have. Instead you get a near neon like glow from the wood. It's like hot coals on steroids. Nuclear orange as I call it.

I love the thing. Comparing it to a regular wood stove is like comparing your GHP to my electric baseboards and electric hot water.