Why No High End Split Geo Equipment?

I think you are missing the big picture here.

Geothermal makes the most sense in new builts, since it avoids the costs of a conventional systems for heating, cooling and domestic hot water.

We are transitioning away from fossil fuel, which means the heating section, which is the second largest emitter after the transportations sector, will have to be electrified.
This will happen in the next 20-30 years, with new built houses being the first where zero emissions will be mandated by building code within the next 5 years, with the retrofit market following about 5 years later.

If I am looking at lets say NY State, that is already law that everything has to be carbon free by 2050 when it comes to heating and transportation, with steps for its implementation.Pretty much everything will be electrified, since that is the only form of energy currently which can be generated renewable and without emissions.

Connecticut is a bit behind with state regulation, but they have set things in motion.

https://portal.ct.gov/DEEP/Climate-Change/Connecticut-Legislation--Executive-Orders-on-Climate

That leaves ASHPs and GSHP, or some crazy guys which use electric resistance.

On a large scale, unless you live in a warmer climate zone (much warmer than Connecticut or New York State), you cannot implement ASHPs. The issue is not overall annual efficiency, the issue is peak. ASHPs simply loose their efficiency and capacity in the coldest hours of the year, GSHPs do not (at least by far not to that degree). ASHPs discharge the heat in the summer into the atmosphere when it is least efficient, only to extract from the air during the coldest days of the year, also when it is least efficient.
GSHPs put it into the ground, where it is stored, and extracts the heat 6 months later. The loop acts as a buffer storage.
The loop is an amazing storage devise. Imagine we would have solar with a battery which can store and supply all the energy needed for 6 months, with a 6" footprint (diameter of the borehole). We would not have a grid anymore...

If we lower the loads of the house, great, we need lesser bore length and a much smaller ground source heat pump. And much smaller ductwork or heads in in terms of a split system. Which will make it much cheaper to install. Lean but mean.

Gas is not cheaper, gas is simply subsidized and socialized. The costs to connect a house to gas is rate based and spread out among all the rate payers, at enormous costs per household. But that infrastructure and those legacy rules are being phased out, and simply not an option anymore. It is actually the costs which drives this transition, in addition to the climate benefits.

 

I agree with Doc.

 

Thanks for posting a well thought out and relevant reply. I don't agree with all of your assessments, but you have clearly thought things out.

I disagree. Geothermal is expensive to put in, when you can build a good quality envelope, get your design loads below 3 BTU/sq.ft., and then cover the load with a couple of mini-split heat pumps. Those homes entirely avoid the costs of a "traditional" heating system, plus they avoid the costs of drilling wells, ductwork, etc, and use a couple of mini-splits and a heat pump water heater.

I certainly hope so. The building codes are woefully behind the curve. The current codes, which have been around for many decades, and are beyond obsolete, result in a design load in Connecticut of around 18 BTU/sq.ft., while current good building practices far exceed code, and will get the design load certainly below 5 BTU/sq.ft., in most cases below 3 BTU/sq.ft. This is part of why geothermal's market is retrofit for the millions of homes already out there, not new construction. The other part of the equation is that in northern climates, where geothermal makes the most economic sense, there just isn't that much SFU new construction going on in the first place.

Geothermal makes a lot of sense in terms of retrofit, as you can tighten up a house with air sealing and some additional insulation, and then go from there with geothermal. However, it only really makes sense in houses that already have ductwork. Houses without ductwork are cost prohibitive to do geothermal compared to current mini-split ASHPs.

I would partially agree with that statement, but partially disagree. Heating is the largest source of emissions in many areas of the Northeast, in large part due to a huge reliance on heating oil and natural gas. There are a number of carbon-neutral renewable fuel sources for heating, however, they don't all scale that well. We have seen during times of high oil prices, high utilization of wood heat. In fact, more homes in the US were heated with wood at one point during the last period of high oil prices than were heated with fuel oil, largely due to a modal shift back and forth in houses that have wood stoves and oil or propane fired heating systems. Wood stoves aren't for everyone, but pellet stoves and pellet boilers are certainly intriguing for certain types of installations. However, they have to be heavily subsidized, as they are extremely expensive to install, and likely make the most sense for apartment complexes and public buildings that have extensive hydronic heating systems and central boiler systems. Wood pellets aren't particularly economical either, as they often cost as much or more than oil. There will be ways in the future to make bio-based diesel fuel, but I don't believe this will play any significant role in home heating, as the fuel will be relatively expensive, and is needed in the form of kerosene for aircraft, on-road diesel for trucking, and off-road diesel for heavy equipment. Where I do think some manufactured bio-based fuels will play a role is bio gas that is a drop-in replacement for natural gas, as well as bio propane as a drop-in fuel for propane.

The problem that many of these solutions face, like with electric cars taking the spotlight from PHEVs, is that a lot of people are seeing it as an all-or-nothing approach, not a pragmatic approach. Many homes would be good candidates for either having mini-split ASHPs installed on top of a hydronic heating system, or as a ducted dual-fuel system, which, converted to burn propane and integrated with a smart grid, could play a significant role in managing grid demand during the dozen or so days a year that it is near design conditions across New England, along with lower emissions and having the capability of burning bio-based synthetic fuels in the future. While oil is relatively easy to replace, as all it can do is run a boiler/furnace or water heater, propane is much harder to replace, and needs a drop-in replacement, as it works really well for a lot of applications like stoves, ovens, heating stoves, wall heaters, patio heaters, generators, grills, dryers, and, of course, heating boilers. Heating boilers need to be supplemented by ASHPs, while pool heaters and water heaters should be replaced entirely with heat pumps.

Connecticut has a particular problem that exists to varying degrees in a lot of states, in that our current grid operator, typically referred to as Neversource (Eversource) owns a power grid that barely works on a sunny, calm day. Most of the grid is decrepit, and has been haphazardly hacked together over many decades, with parts operating today that were installed during the Truman or Eisenhower administrations. Wires literally fall off of poles and burn on the ground, transformers explode seemingly for no reason, every time there is a small storm, half the state loses power. That's a huge hurdle to overcome. While grid reliability and implementing a smart grid are two different and distinct issues, widespread electrification of heating and cars and implementing a smart grid on a system that's poorly maintained and barely works today is even more of a challenge than it would be a well maintained, modernized, and resilient system.

 

So that's true at an extent. Yes, ASHPs lose efficiency at near-design temperatures, which is why I think hybrid dual-fuel systems have to be a large part of the answer, as the grid simply cannot handle the demand from electric strip backup, even if it were massively upgraded from it's current state, and significant additional baseload nuclear generation, along with peaker generation burning stuff were put in place. I think that once-through peaker turbines are going to be needed long into the future, but instead of running on hot, sunny days, as we move to put more solar everywhere, they will be run on dark, cold, nights. In the future, it's not technically difficult to run them off of bio-based kerosene, and while they would consume vast quantities of fuel, it would only be for a handful of days a year. Traditional boiler-based steam plants could also be utilized to an extent, burning stockpiled biomass, which is easy to store, as it can just sit there in huge piles waiting for a cold snap.

Looking at the very big picture, there is value for a lot of applications to use pure electric systems, be they ASHP or GSHP, and tolerating some level of massive peaker demand on the grid, but if many houses have local dual-fuel integrated with smart grid, it will be much easier to manage. Even with only a small fraction of homes using electric heat (although a lot of boilers and older furnaces chew up a lot of power in order to burn fossil fuels), during the polar vortex of 2017-2018, New England's gas supply problem combined with high electricity demand caused ISO NE, which normally uses a very small amount of oil and coal, to have to call upon power plants to burn thousands upon thousands of tons of both fuels.

Back to heat pumps themselves, yes, ASHPs lose efficiency at near-design temperatures, with the Mitsubishi mini-splits dropping from a seasonal average of roughly 3.2 to 1.7 at 0F, and Carrier Greenspeed, with a seasonal average COP of 3.8, dropping significantly to some number that they won't disclose, but also losing significant heating capacity below 20F ambient. The mini-splits, however, are underrated in terms of efficiency. While their raw COP and SEER ratings are not that impressive compared to Greenspeed, I do believe that they are actually significantly more efficient, at least in New England for three reasons. First, the mini-splits allow for room by room control, which in the summer will cut some rooms' energy consumption by nearly 100%, as they don't need to be cooled, and can save significantly in the winter as well, especially during the majority of the winter where it is 30-50F outside and some rooms can be kept at 50F-55F while not in use. New England is actually a great climate for mini-splits, as they can heat all winter, and we need AC, but not necessarily in every room all the time. We also have long shoulder seasons where parts of a house can remain unheated until we hit 32F outside, and parts of a house can remain uncooled most of the year. Secondly, mini-splits don't have duct loss due to ducts in unconditioned spaces. Third, mini-splits don't have zoning imbalance problems, as each head runs its own zone.

Geothermal is significantly more efficient for centrally ducted systems, although over the course of a year, I doubt that it is much more efficient than mini-splits, even when GSHPs have a COP of 5.1-5.3 versus 3.2 for the mini-split, and an EER of 40-45 versus a SEER of 17-19 (how to convert between SEER and EER for modern equipment is unclear, most of the charts end well short of the EER of modern GSHP systems). Where it holds a significant efficiency edge is over ducted ASHPs, which suffer from the same inefficiencies in a ducted system as geothermal, although with Greenspeed, the extra cost of drilling wells makes geothermal a tougher sell. The advantage for GSHPs from a grid perspective is that they don't peak up their demand nearly as much as ASHPs, and if installed properly, shouldn't need strip back up at all, even at design temperatures. While GSHPs may be sized a bit shy of the design load, the design load is BS, as the calcs don't account for the thermal capacitance of the building, the people and stuff in the building heating it up, and they are based on grandma having the heat blasting at 70F. Similarly, the AC load calcs get more and more screwed up the farther north you go, as the building is less load than all the people and stuff in the building, although that's a concern for commercial installations, not residential.

So to loop back to new construction, there is no need to put a GSHP in a well built new construction modern house with a design load of 3 BTU/sq.ft. It just doesn't add up. It's too expensive compared to some mini-splits. Drilling wells, installing ductwork, all of that, it makes no economic sense. When you're talking about retrofits where you have 25 BTU/sq.ft. and you can get it down to 15 or 20 BTU/sq.ft. with insulation and air sealing, then GSHPs start to make a lot of sense. The new construction situation might make sense with mini-split GSHPs (although how much does it cost to bring a drilling rig out for a 150' well?), but AFAIK, no such system exists today for residential use, and while I do firmly believe there is a market for split system high-efficiency GSHPs that can be configured with dual fuel, I'm not sure there is much of a market for mini-split GSHPs, as mini-splits are often installed in smaller, older homes where cost is a primary concern, and something fast, cheap, and minimally invasive is desired, which mini-split ASHPs achieve, but mini-split GSHPs would not.

So most new homes in CT are on LP gas, not natural gas, as there isn't a significant NG distribution system outside of the urban areas and some of the denser suburbs, and even then it doesn't cover a lot of areas that have water and sewer, and covers almost nowhere without water and sewer, as the density just isn't there. The crappy cardboard houses out there by and large have LP gas, with a few on NG, and few that are well built, and few with ASHPs or geothermal. Gas is cheaper to install up front, even though it's much more expensive in the long run, and in parts of CT, it's $22/mo just to have a gas meter sitting there, which ends up being a significant cost over time just to have a meter so that you can actually buy the NG. The cheapest thing to install in a house is an ASHP, the next thing being gas, with GSHPs being by far the most expensive.

On the grid side of it, I have to wonder at what point gas grids stop making sense. If we were to electrify most of our heating and hot water, does it make sense for the gas company to maintain a gas grid for cooking, occasional peak heating usage, and a few other miscellaneous things here and there or does it make more sense to convert a lot of areas over to LP gas for those small uses? I'd imagine for cities and for MDUs where you have a high density, a gas grid still makes sense, and LP gas is impractical, but for areas that are entirely SFUs, I have to wonder. We also have the methane problem, as some of these gas systems are way beyond EOL, and are poorly maintained at that, but those areas typically have the houses that entail the most work to convert to heat pumps as well.

Part of the problem is user education. At least GSHPs have a good name, as ASHPs have been trashed over the years, due to poor user education, with people hearing horror stories of the older ASHPs that don't work much below 20F, instead of modern ASHPs that work well below zero, albeit with significantly reduced efficiency. Smarter people are starting to catch on to mini-splits being extremely efficient, and people are getting them to add AC, and then using them for heating for most of the season, only running oil or gas fired systems during cold snaps. Unfortunately, few people understand building practices, and how to properly insulate a home. There are all sorts of crooks out there selling "energy efficient" homes that have 2x6 walls and fiberglass insulation in them, and then there are the people who think that scorched air furnasties or hydro air are somehow more "luxurious" than hydronic heating systems, even though that's the exact opposite of reality for the vast majority of applications (outside of modern high performance houses).

 

As we all know, to get to 5 BTU/sqf you need to invest $$$ and you get quickly to the point of no return. We built about 30 net zero houses per year which are at about 8-10 BTU/sqf for peak heat load, and the formula is pretty simple:

1) make good envelope improvement beyond code minimum to save an additional 30%
2) pop in a geo system for space conditioning and hot water which saves you about 50%
3) the 20-30% remaining you put a solar roof on, and you are at net zero energy and zero emission

The premium cost over code minimum is about 3-5%.

More tomorrow, it seem to take some time to explain, and I am tired....

 

Sure, it costs more to build a house to modern good building practices (which will fall in the 3-5 BTU/sq.ft. range), as opposed to the R-19 cardboard houses that are the code requirement. In fact, it costs thousands or tens of thousands of dollars. However, most of the net zero energy homes being built don't have ductwork or HVAC systems in the traditional sense, as they rely entirely on mini-splits, and there is good reason for this. Once you're in the 3-5 BTU/sq.ft. range, you save tens of thousands of dollars on running ductwork, piping, drilling wells, etc, even after factoring in the cost of a mini-split system. You can buy a lot of 2x8's and dense-pack cellulose for the price premium of a ducted geothermal system and wells over a simple mini-split system.

So that approach will yield about the same energy efficiency as a home that's better built but uses ASHPs, but at what cost and complexity? Building a house that can be heated with a single 1 ton minisplit and doing hot water with a heat pump water heater is fast, cheap, and relatively easy. Sure, you have to spend some more money and effort in building a good envelope, but the end result is both better and cheaper. For very large, high-end custom projects, maybe it makes sense to combine an envelope that's below 5 BTU/sq.ft. with a central geothermal system, but that's beyond the point of economics, and built for energy efficiency and comfort, not being economical.

In terms of code, the code should require all new houses to be net zero energy, which would require significant improvements to the building envelope. I'm not sure I'd want the code to force building at 3 BTU/sq.ft., but if there are energy consumption levels that are set that are roughly equivalent to 5 BTU/sq.ft. with mini-splits or 10 BTU/sq.ft. with geothermal, the former is going to win out for most projects due to cost and simplicity. It would, however, need to set some standards on energy consumption that are beyond the current junk required by code, as you wouldn't want to incentivize building cardboard houses, slapping a cheap ASHP in it, and then putting a whole ton of solar panels in the yard just to offset the energy consumption.

 

Yawn

 

Gentlemen

This thread has gotten way off topic and does not serve anyone who may be interested in the application of newly available "High End Split Geo Equipment". I suggest you start a new thread, appropriately named, if you wish to continue your discussion.

Mr. Wood

The Waterfurnace Series7 control system will accept a "W" to engage Emergency Heat. A hot water hydrocoil can be mount on the outlet of the packaged unit or split AHU and be enabled with an isolating relay to the boiler control system. We do it all the time in houses with hot water boilers and not enough electric service (or generator capacity) to support electric backup heat.

Mating any HP (geo or air source) to a gas furnace has it's own challenges. By definition this is a dual fuel system (refrigerant coil on the outlet of the furnace). Furnace manufacturers do not allow AC air to the furnace inlet because condensation can corrode the furnace heat exchanger. Due to the refrigerant coil location in a dual fuel application the heat pump must be disabled while the furnace is in operation. Simply put the HP can not heat already heated air.

Any VS system has to have complete control of the blower motor. This can only happen if a furnace manufacturer fully integrates their fan control with a geo manufacturers VS control system. The market share is just not there to make it happen.

 

Very interesting. That opens up a lot of possibilities for various combinations of systems, but weirdly is not mentioned in the literature or documentation for the WF Series 7. By boiler control you mean the hydronic zone board that controls the boiler pumps or valves?

Right, but it makes no sense to have the heat pump and scorched air furnasty running at the same time anyway. Carrier has such a system for their Greenspeed ASHP, but I could see why it would be too niche of a market for a GSHP only. It seems like a missed opportunity for Carrier, since they already have the rest of the system, they could make a split variable speed geothermal heat pump and mate it with an existing furnace or air handler with communicating controls. So when the Series 7 is mated with a hydronic coil, does it run the fan at full speed for whatever zones are running at that point in time to maximize heat output from the coil? Presumably, the idea with geothermal would be to use the hydronic coil only a handful of days throughout the year or during power outages?

What's really scary right now in CT, due to COVID is that fuel oil is cheaper than the seasonal average running the best ASHP, and only marginally more expensive than a GSHP. The ASHPs are still probably cheaper for shoulder season. Clearly that won't be the case forever.

 

The application of a hydro air coil is 3rd party and would not be documented or supported by Waterfurnace, anymore then Chevy would document and support the installation of a cat back MagnaFlow exhaust system on your pickup truck.

Yes. An isolating relay can be activated by EH1 or EH2 on the Aurora control board (normally used to activate the electric heat strip relays). The dry contact from the relay is wired to the hydronic zone board to activate the appropriate pump or valve and enable the boiler.

Carrier does not manufacture residential geo equipment. They put their badge on someone else's equipment. It used to be ClimateMaster but I believe it is Bosch/FHP now.

Yes. An Aux heat call will engage the fan at the Aux fan speed as setup on the Aurora control board. With IZ2 Zoning, any Aux or Emergency heat call will open all zone dampers and set point temperature is controlled only by the MasterStat. There would be no control of the hydronic coil except for on/off.

 

As I read this discussion, couple thoughts came to me.
Mandating net zero or something close to it in home construction will effectively move home ownership even higher in the economic strata. We also need to recognize that many (probably most) of the net zero homes (and a good portion of the GSHP's) are being built by those to whom the cost is not a large part of the equation. It's easy to be "green" when you have the money! I'm painting with broad strokes here, but there is at least some truth in that. The low middle class often simply can't afford to even consider the sizable up front cost of GSHP or net zero.

We have a $75000 1400 sq ft modular home on a finished basement. Counting the basement area our design load is 8-10 btu per sq ft. We are running a 3t geothermal (it is oversized. Never runs on hi to maintain temp) on a horizontal loop which I installed myself for approximately $14000 including new ductwork. Total household energy requirements are $1200-1500 per year. ASHP or mini splits may have been a little cheaper but the comfort and simplicity of one thermostat and one system is worth something too.
My point is, one size does not fit all. I'm a big fan of the GSHP, but if we had had a NG line hookup option, GSHP would have been a much harder sell, cost wise.

 

Yet there is clearly demand for such an application, so they should officially support it as they do for some of the lower performing models. The thing is geo is that due to the high up front cost, you really need the highest end equipment to make it make economic sense.

That's interesting, as they've got their two-stage geothermal equipment all integrated with their air handles, thermostats, and humidifiers.

If they officially supported, couldn't they set it up so that it could still zone while using the hydronic heat, just providing max CFM for the zones that are currently calling?

 

There are several aspects to this notion, but the notion at it's heart is inaccurate. So the first issue is that we have to deal with the climate crisis, and continuing to build crappy cardboard houses is not the way to deal with it. However, when you look at the economics, a net zero home built to 3x code that can be heated with a couple of mini splits is about the same cost as crappy cardboard bare minimum code construction, due to the lack of ductwork, piping, etc, that comprises a "traditional" HVAC or heating system.

Whatever small, marginal cost might be added to the home is going to be recouped within a very short period of time in lower energy costs. That small marginal cost, if it exists at all, which it may compared to a bare minimum house built without A/C, and just built with propane and baseboard hot water heat or something, can be completely eliminated if you involve the lender, so that the mortgage can be made slightly larger, recognizing that the energy costs will be effectively nothing, resulting in a lower total cost every month. Lastly, on the generation (solar) side of things, there are already financing mechanisms available, and today, with net metering, it is cheaper to finance a solar system, even fairly far north, than it is to buy the power from the utility, so that is again simply a matter of figuring out the financial mechanisms to have the lender transfer the loan from the builder to the homeowner, to wrap it into the mortgage, or to have the solar company hold on to it until the house is sold, and finance it directly to the homeowner. Yes, financing solar panels technically defeats the concept of net zero energy being owned and paid for without recurring costs, but if a house costs an extra $50/mo with $150/mo to finance the solar, but saves $150/mo in electric and an average of $150/mo on propane, than the homeowner still comes out way ahead at the end of the day, and has a more comfortable house to live in.

You also have to look at what new construction is today, and that is mostly higher end houses or multifamilies to begin with, so this question is largely hypothetical. What would make an impact for orders of magnitude more people would be financing, incentive, and subsidy mechanisms for existing homeowners to upgrade the energy efficiency of their homes, and partially or fully electrify their heating.

While that's fine for looking at DIY options, that's not a valid cost comparison of the various systems, as you'd have to include the cost of the well drillers and tin knockers to do a fair comparison of the installed costs. There is a lot of labor that the tin knockers have to do, and the well drilling is pricey to bring in a huge drill rig for a day or three to drill the wells. There certainly are a lot of advantages to geo, I would argue that room by room control is a big advantage of mini-splits, at least in houses where you have discreet rooms. If you've got a big open floorplan area, then a centrally ducted system is probably going to work better.

 

I would hate to force people to buy high end equipment. Most people can't afford geothermal ground or minisplits – they're both extremely expensive, for reasons I don't understand. California is a great example of what happens when a government dramatically increases the cost of housing – home ownership is just out of reach for most people, especially young people. It's a disaster.

There seems to be a bit of an East Coast or Northern skew here. Natural gas is actually pervasive out West, and cheap. Texas, for example, will never coercively ban gas or other affordable options, so these prophecies of zero carbon legal regimes are strange. We don't need zero carbon anyway. Even a 50% drop would be great, and we'll obviously get there without any sweeping bans. And don't forget that industry needs lots and lots of gas, so it's never going to just be about cooking or niche uses.

I'd like to see a lot more high-end and low-end ground geo. The equipment is eye-wateringly expensive, and so is the drilling. I just posted an Oak Ridge report on prospects for reducing the drilling cost. I wonder if there's a way to move in a DIY direction on the drilling, the way people rent backhoes and so forth. If a loop borehole driller was something we could rent and reliably use, that would be something. It seems like drilling a borehole should be much easier than digging out a basement, with fewer variables.

Also, if it could be automated that would help cut costs. There's a lot of innovation right now in automated tractors, excavators, etc., like Build Robotics, and the task here seems a lot simpler than conventional construction, with a lot less movement and fewer variables for the AI to deal with.

We might need upstarts to get good high-end equipment at much lower prices. It's not rocket science. We could launch a crash engineering program to tackle the problem from every angle and figure out how to produce long lasting equipment at much lower cost. The incumbents seem pretty lazy and content with the status quo market equilibrium, where hardly anyone has ground geo. If an Elon Musk type tackled the problem, we'd get much better results, but there's a shortage of Elon Musk types out there. We need to get the costs way down, like that South American solar water heater project. We might need regulatory reform as well, to clear the way for cheaper install. Digging a loop needs to be as normal as planting a tree.

 

The efficiency standards need to go up, and need to go way up, but that's not really the point of this discussion. Allowing SEER 13 and 14 central air conditioners and heat pumps is ridiculous when the industry can produce SEER 24 units, and air source is the majority of the market. Just cranking up the efficiency standards would save people a TON of money. In terms of ground sourced equipment, you have to get up to a COP of 5 and EER of 40 in order to make the equipment even have a prayer of being economical compared to air sourced equipment due to the astronomical cost of drilling wells. Geothermal reigns absolutely supreme in terms of raw efficiency, but it has a hard time staying economical due to the massive up front costs versus an air sourced heat pump with a COP of 3.8 and SEER of 24 that you can just plop down and install. Your comments about home ownership make no sense, as a well built modern house with mini-splits doing all the heating and cooling will have a MUCH lower TCO over even a fairly short period of time. The only change that would be needed to account for any small, marginal amount of additional up front cost to build the houses be energy efficient in the first place is on the financing side to allow slightly larger mortgages for net-zero homes that have no energy costs other than the $10/mo for the electric meter. For replacements and retrofits, marginally more expensive equipment will save a lot of money over a fairly short period of time, and again, all you need to do is tweak the financing mechanisms to allow a portion of the savings to go to the financing payment, and the homeowner keeps the rest of the efficiency gains.

Yup. Because that's where the heating challenges are. LA basically doesn't need heat (ASHP for once in a blue moon), most of the rest of CA would be fine with ASHPs, as would the south, which is why many houses down there are built with ASHPs to begin with. It's the Northeast where things get challenging. We absolutely have to get to zero carbon. We cannot keep dumping carbon into the atmosphere like it's a giant garbage dump. We can create zero carbon biogas to an extent, it's already done in Europe, but it's not going to scale anywhere close to our massive consumption of gas today. Further, gas is simply not economical to distribute in a grid. Just having a meter sitting there doing nothing is $22/mo, and it's more expensive BTU for BTU than a high efficiency air sourced heat pump is. And it's worse than that, as the heat pump has all of it's electricity factored in, the gas air scorcher still needs electricity to run the blower after it consumes that expensive gas connected to that expensive gas meter. By the time it's all said and done, a 95% gas air scorcher costs 30-40% more to operate than a Carrier Greenspeed ASHP. It's more expensive to install all the gas lines. The problem is consumer education. People don't sit there and do the math out, and there is a myth that gas is cheaper than heat pumps because people still have the awful heat pumps from the 1970's and 1980's in their heads, where they'd have to run strip heat a lot when below freezing, not Carrier Greenspeed where they can run to -30F, and average a COP of 3.8, or the Mitsubishi Mini Splits that can't hit the same efficiency numbers, but offer much better zoning and control. The other economic reality is that houses without ductwork aren't economical to refit with ductwork, so they will naturally go to the mini-split heat pumps with a gas fired backup system.

Probably the most perplexing challenge to getting rid of gas is restaurant kitchens. Obviously many use propane, so they don't need a natural gas grid, but that's just another fossil fuel that burns like gas. Probably the long term solution is bio-propane for niche applications where gas is needed, like cooking, patio heaters, fireplaces, etc, etc. Steelmaking and some other industrial processes are going to be a challenge to figure out, especially since new steel is mostly still made with coke.

There's no economical or efficiency argument for geothermal with a COP less than 5 and an EER less than 40, and even then, it's maybe coming out a decent cost advantage in year 16 when you factor in the equipment lasting 30 instead of 15. The up-front cost is astronomical, even with subsidies. I think it should be encouraged from a policy perspective, but only the very most efficient systems. In theory, a WF7 shouldn't really cost any more, or even as much as a Carrier Greenspeed of the same tonnage, as they are basically the same technology, just with water versus air providing the heat source and sink.

 

Dandelion Energy, a Google startup, is attempting to reduce the drilling/excavating costs in NY State along the lines of what you are searching for. Its a relatively local area they are focusing on but the key to it being palatable is that no more natural gas hookups are being allowed in the area (they also have some state subsidies in addition to what is left of federal subsidies). Without natural gas, people's choices are electric, propane, or oil. And given those choices, electric based geo can make inroads especially if the ground work cost part can be reduced. I'm not aware of anywhere that natural gas is expensive (on a relative basis) and that is the problem for geo. Geo mostly excels where natural gas isn't available because the alternatives suck and/or are just as if not more expensive when looked at over long term (installation+operating cost). Dandelion is mostly successful at this point do to the cheap financing that can be obtained via Google but I believe the attempt is to streamline installation so each house isn't different (they all get a variable speed 5 ton unit as an example), wells are pre-drilled on a community wide basis, etc. so every house isn't a one-off installation. Everything in geo seems like niche contracting (at least currently) so that is certainly driving up the cost. But the flip side to it also is that as soon as it cheapens somewhat, demand increases, more contractors will come rushing in (with no design skills) and there will be a lot more problem installations than there are now, geo gets a bad rap, and the cycle continues. Its truly the one thing I have run across in residential construction that really needs experienced designers of the system and from my own personal experience, people with seemingly lots of geo experience had zero design ability. I got lots of blank stares when asking pointed questions about things that I think would be mundane issues for a functioning geo system.

 

I have seen Dandelion Energy. They have an interesting rig that they use to drill. In Connecticut, about half the state doesn't have natural gas, because there are no natural gas lines, and where there are, it costs 30-40% more to operate than a high efficiency air sourced heat pump, much less a ground sourced heat pump. Propane costs significantly more than any of those options. I haven't done a full update of my energy cost spreadsheet, but electricity has only gone up a tiny bit, and gas has gone up more, which is how we got to gas being more expensive than heat pumps. And that doesn't account for installing solar and bringing your electricity cost down for ASHPs or GSHPs.

I suppose that crappy installations affect geo a lot more than gas or oil, but most gas and oil systems are poorly installed, improperly sized, etc. The ductwork is another challenge, as a lot of ductwork isn't in very good condition, so it really needs to be tightened up and balanced properly before geo is going to work well in that house. Gas- and oil- fired hydronics are notoriously bad for poor design, improper sizing, etc, it's just that most people don't know the difference, and they don't know how a properly designed and installed system should work. I would think the only way to enforce proper training is a company like Waterfurnace requiring their own training and certification to install their products, similar to specific training that Carrier offers for Greenspeed.

 

[QUOTE="I suppose that crappy installations affect geo a lot more than gas or oil, but most gas and oil systems are poorly installed, improperly sized, etc. The ductwork is another challenge, as a lot of ductwork isn't in very good condition, so it really needs to be tightened up and balanced properly before geo is going to work well in that house. Gas- and oil- fired hydronics are notoriously bad for poor design, improper sizing, etc, it's just that most people don't know the difference, and they don't know how a properly designed and installed system should work. I would think the only way to enforce proper training is a company like Waterfurnace requiring their own training and certification to install their products, similar to specific training that Carrier offers for Greenspeed.[/QUOTE]

I hired a well known contractor who actively advertises as a first class geo installer. On top of that, they were recommended to me by a neighbor who says they have done good service on his system. Ok, what do I know so I go with this contractor. This contractor supposedly did a heat loss calc and designed the system before giving me a quote. A few things seemed off so I asked some questions. Turns out it was all done via several software programs that said contractor had no idea how to use. I spent ~2 hours troubleshooting his input to the program at his office with him at which point his numbers still didn't make sense and he didn't want to spend any more time "designing". So I took over design. He ultimately didn't care because I sized a slightly larger system (3T+ 4T units whereas he had 2-3T units) and a significantly larger ground loop (1200ft of vertical wells vs ~700ft he had come up with) and I paid him to install the bigger system so no skin off his back After this, I ran across several other people with similar sized homes in my area that he quoted the exact same system and price too (apparently not doing any "design"). Fast forward to the installation, turns out said contractor had never installed a two unit system prior (I can't imagine this is that uncommon) and was confused how to set up the header/pumping arrangement. So they brought in a Waterfurnace employed area rep who they claimed was an expert in ground loops and pumping. His solution was to install three flow centers for the two unit system. I nixed that too and gave him my head loss calculations showing 1 variable speed pump on each unit would be more than adequate . I don't think he understood the head loss calcs and begrudgingly "allowed" it. Fast forward a year, and the thing not only works but is as efficient as was predicted by my weather bin analysis using at the time current energy pricing for natural gas, electric, and propane. I actually was pushing for 1 variable speed pump for the whole loop but the several pumps they use weren't able to meet that head loss/flow requirement - to be upgraded when one of the pumps goes.

Gas and oil fired systems are a lot harder to screw up because they will get air hot. Maybe they short cycle and burn out quicker than they should (so 15 years instead of 20) or maybe the duct work is too small (which could be a problem in geo too) so you get cold spots but by and large they will heat your house. Screw up the plumbing in geo, and best case you waste a lot of money on pumping water destroying all promised efficiency and worst case the heat pumps don't work even when the heat pump is wired to a source of electricity (ie the fuel). Or maybe too short a length of ground loop in installed (because this is expensive to install and if we could just use a little less...) and the heat pumps sort of work and then electric backup kicks on for a long period destroying all the promised efficiency. A lot can go wrong in geo and most people don't like to do math. Its a bad combination.

 

That's wild, usually contractors oversize equipment, not undersize it, but I guess when you're doing geo, there is an incentive to undersize it in order to bring the up front costs down, versus gas and oil, where it's barely more to put in a 100k BTU or 150k BTU system where a 60k or 80k unit would do the trick just fine.

Gas and oil is easy to screw up, most people just don't know that heat isn't supposed to scorch the air in 2 minutes, shut off, get cold 20 minutes later, and repeat the cycle, because they've always had poorly installed oversized systems. Most ducted systems are wildly imbalanced, regardless of what they are doing, heat, A/C, both, heat pump, gas, oil, etc. Hydronic systems are another level of screw-up, and steam is even worse. Most hydronic systems are wildly oversized, sometimes with imbalanced radiation to boot. And often the boiler piping isn't even done right. Get to outdoor resets and variable speed pumps, and it goes farther off the rails. While the consequences of screwing up a gas installation and losing 5-10% efficiency is a lot less than in geo, where you end up on strip heat that's 5x the cost of geo, I think that the problem is basically the same- lack of knowledge about how the systems actually work, and lack of willingness to sit down and do it right.

 

Dandelion.......
As a business model it would fail horribly without the subsidies and the prohibition on NG hook ups. They touted " A revolutionary new drill " to get it done. Guess what? Sonic is not new, and the videos posted on you tube by homeowners show case a horribly in effeciant process. So much so it makes my eyes bleed just watching it. Doc Jenser will also tell you they came into his market place and told everyone who would listen " that they are going to squeeze every possible dollar" out of any sub contractors
Drilling by an experianced driller is very cost effective when it comes to loops. I would also point out that in many places drilling is not the best choice for a geothermal exchange.
Eric