My bet is the consensus here will be that the money would be far better spend on improving the envelope, and a mini split or 2 if AC is desired. 如果有天然气，这是加热最便宜的方式
My experience has been mini splits are definitely cheaper than both oil and gas. The monthly connection charges and fees here are like $25 a month or $300 a year before you even use any gas. I have net metered solar but If I had to purchase the power I would have spent less this winter so far than just the connection charges alone to run my 2 12k mini splits. I use a heat pump water heater for hot water which is way cheaper and efficient to run than gas as well.
>"Is natural gas cheapest? Consensus here seems to be that mini-splits are cheapest."
At MA type (nearly the highest in the nation) electric rate and (also pretty high) natural gas rates it's cheaper to heat with condensing natural gas, with margin.
No matter what the solution, the first and most critical thing to get right is the load calculations. Do NOT let the HVAC contractor (especially a geothermal contractor) run those numbers- hire a certified P.E. who regularly does Manual-J calculations as a service, and make sure they understand that due to the extreme expense of geothermal it needs to be done as aggressively as possible. Also solicit suggestions for cost-effective upgrades to the building envelope, with the load numbers of the "after upgrades" version of the house.
>“我喜欢在窗户外面没有嗡嗡作响的压缩机。我相信它的固有敏感性意味着它将是有效的。”
With the exception of Dandelion Energy (not currently operating in MA), every geothermal system is a custom-designed system, fraught with design error risk that can bring even the best water to water heat pump to it's knees for as-used seasonal efficiency. Vet your contractors VERY carefully. There is a lot of pumping energy needed to move that ground source loop, and high velocity air handlers can chew through a lot of power too. Even though a perfectly designed perfectly implemented low-temp hydronic geo system can hit a seasonal COP north of 4.5 (HSPF 15) for the whole system, all power included, in a retrofit that requires a substantial amount of low-temp radiation. A more realistic expectation would be an average COP of 3.5 (HSPF 11-ish), which is pretty easy to hit with air source heat pumps in a MA climate.
Air source heat pumps with scroll compressors don't buzz (though not totally silent, they're pretty quiet), and there is no reason to install them outside your window. Most noise issues with mini-split compressors is the low frequency vibe when the unit is mounted to the wall. There is no reason to mount it on a wall either, but you DO want to mount it high enough that the bottom pan is above the record high snowpack depth in your area.
The real performance difference between best-in-class air source heat pumps and geothermal isn't average efficiency, but rather the efficiency at peak load. When it's sub-zero outside the geo system will still be hitting it's COP 3.5-4.5, whereas a best in class air source heat pump will be running a COP of 2. But binned hourly mean outdoor temps in January in almost all MA locations are north of 20F (it might be cooler than that on the summit of Greylock in January) and in coastal locations they're north of 25F, and in the Cape & Islands north of 30F, and that's just the coldest month. Properly sized an air source heat pump really CAN hit a seasonal average a COP of 3.5, even if it's burning nearly twice the power of a better class ground source heat pump system when it's below 0F. But the total number of hours in a year that it's below 0F in any MA location is mini-scule, and doesn't much affect the average efficiency.
While I'm generally in favor of efficiency improvements, I'd argue that if you're not going to make those improvements, then the more inefficient the house the more sense a high-efficiency heating source makes.
我是一个人数。要说服我，您必须向我展示计算，这东西不会在现实中节省太多能量。
I'd add that you have a business opportunity to sell some efficiency improvements to the house. If I'm installing a whole new HVAC system, and tightening the envelope allows for a smaller system that costs less, the payback period for those improvements is right now. With geo the biggest cost is the wells, and you need a certain amount of well per ton. There's a very direct proportion between system size and cost. So if the installer says, "with the house the way it is you need a 3-ton system which costs $30,000, but if you insulate the attic you'd need a 2-ton system which costs $20,000, and insulating the attic costs $5,000," that's a pretty compelling case for insulating.
>"There's a very direct proportion between system size and cost. So if the installer says, "with the house the way it is you need a 3-ton system which costs $30,000, but if you insulate the attic you'd need a 2-ton system which costs $20,000,"
那永远不会发生。
A 3 ton system only rarely comes in at $30K, and a 2 ton system literally never comes in at only $20K. If those are the kinds of numbers they are using it's time to get VERY skeptical about the competence. There is a base cost they need to recover for designing the system that doesn't change with the bill of materials or the depth of the wells, and it's not cheap. Most contractors will still want to oversize the system even when handed a third party Manual-J performed by a competent engineer.
In this MN study involving in-situ monitoring of dozens of GSHP installations, the heating seasonal performance median was a COP of 3.19 (~HSPF 11) and the 75th percentile was a seasonal COP of 3.75 (HSPF 12.8). The 25th percentile was a none too impressive COP 2.88 (HSPF 9.8) See Table 7, p33 (p44 in PDF pagination):
I can definitely say that there is no way to justify the cost of even getting one more drilled, never mind the two needed to get near the capacity to heat the place with a GSHP.
Compared to even the cost of a brand name cold climate heat pump, the extra bit of efficiency improvement, the ROI on just drilling the wells alone, never mind the equipment is many many decades.
>"Just to be Contrarian, is it fair to compare the average installed performance of ground-source with the specified performance of air-source? Air-source installers mess up too."
Get realistic quotes for you client, double check them with actual installs, don't let a contractor underbid and then add on. Get references, with prices.
“My client currently has oil forced hot water.” Is the current system forced air with domestic hot water or is it an oil boiler feeding hydronic heating loop?
对于强迫空气而言，收回电力节省的井钻孔成本比较超热量小型分裂的不太可能。
For geothermal the pump usage is a total wild card. The horse power is random choice of the installer. The loops and wells are all different from one sire to the next.
答复
My bet is the consensus here will be that the money would be far better spend on improving the envelope, and a mini split or 2 if AC is desired.
如果有天然气，这是加热最便宜的方式
是的，我同意，但不幸的是我的客户没有。也没有天然气。
天然气最便宜吗？这里的共识似乎是迷你切片最便宜。
My experience has been mini splits are definitely cheaper than both oil and gas. The monthly connection charges and fees here are like $25 a month or $300 a year before you even use any gas. I have net metered solar but If I had to purchase the power I would have spent less this winter so far than just the connection charges alone to run my 2 12k mini splits. I use a heat pump water heater for hot water which is way cheaper and efficient to run than gas as well.
>"Is natural gas cheapest? Consensus here seems to be that mini-splits are cheapest."
At MA type (nearly the highest in the nation) electric rate and (also pretty high) natural gas rates it's cheaper to heat with condensing natural gas, with margin.
地热也倾向于在MA上运行$ 9-10K/吨（更昂贵的1-2吨系统），这非常昂贵。如果在MA（Nat'l Grid，Eversource）中的较大且更昂贵的净计算业务之一上，使用空气源热泵 +屋顶PV通常更具成本效益。
No matter what the solution, the first and most critical thing to get right is the load calculations. Do NOT let the HVAC contractor (especially a geothermal contractor) run those numbers- hire a certified P.E. who regularly does Manual-J calculations as a service, and make sure they understand that due to the extreme expense of geothermal it needs to be done as aggressively as possible. Also solicit suggestions for cost-effective upgrades to the building envelope, with the load numbers of the "after upgrades" version of the house.
>“我喜欢在窗户外面没有嗡嗡作响的压缩机。我相信它的固有敏感性意味着它将是有效的。”
With the exception of Dandelion Energy (not currently operating in MA), every geothermal system is a custom-designed system, fraught with design error risk that can bring even the best water to water heat pump to it's knees for as-used seasonal efficiency. Vet your contractors VERY carefully. There is a lot of pumping energy needed to move that ground source loop, and high velocity air handlers can chew through a lot of power too. Even though a perfectly designed perfectly implemented low-temp hydronic geo system can hit a seasonal COP north of 4.5 (HSPF 15) for the whole system, all power included, in a retrofit that requires a substantial amount of low-temp radiation. A more realistic expectation would be an average COP of 3.5 (HSPF 11-ish), which is pretty easy to hit with air source heat pumps in a MA climate.
Air source heat pumps with scroll compressors don't buzz (though not totally silent, they're pretty quiet), and there is no reason to install them outside your window. Most noise issues with mini-split compressors is the low frequency vibe when the unit is mounted to the wall. There is no reason to mount it on a wall either, but you DO want to mount it high enough that the bottom pan is above the record high snowpack depth in your area.
The real performance difference between best-in-class air source heat pumps and geothermal isn't average efficiency, but rather the efficiency at peak load. When it's sub-zero outside the geo system will still be hitting it's COP 3.5-4.5, whereas a best in class air source heat pump will be running a COP of 2. But binned hourly mean outdoor temps in January in almost all MA locations are north of 20F (it might be cooler than that on the summit of Greylock in January) and in coastal locations they're north of 25F, and in the Cape & Islands north of 30F, and that's just the coldest month. Properly sized an air source heat pump really CAN hit a seasonal average a COP of 3.5, even if it's burning nearly twice the power of a better class ground source heat pump system when it's below 0F. But the total number of hours in a year that it's below 0F in any MA location is mini-scule, and doesn't much affect the average efficiency.
所以我是那个家伙。我要在我的新房子里地热。我的想法是，它在最热的一天和最冷的夜晚都与其他任何时候一样工作。我喜欢这样的想法：一旦钻了孔，它将永远持续下去，只需定期更换压缩机即可。我喜欢在窗户外面没有嗡嗡作响的压缩机。我相信它的固有敏感性意味着它将是有效的。
While I'm generally in favor of efficiency improvements, I'd argue that if you're not going to make those improvements, then the more inefficient the house the more sense a high-efficiency heating source makes.
我是一个人数。要说服我，您必须向我展示计算，这东西不会在现实中节省太多能量。
I'd add that you have a business opportunity to sell some efficiency improvements to the house. If I'm installing a whole new HVAC system, and tightening the envelope allows for a smaller system that costs less, the payback period for those improvements is right now. With geo the biggest cost is the wells, and you need a certain amount of well per ton. There's a very direct proportion between system size and cost. So if the installer says, "with the house the way it is you need a 3-ton system which costs $30,000, but if you insulate the attic you'd need a 2-ton system which costs $20,000, and insulating the attic costs $5,000," that's a pretty compelling case for insulating.
>"There's a very direct proportion between system size and cost. So if the installer says, "with the house the way it is you need a 3-ton system which costs $30,000, but if you insulate the attic you'd need a 2-ton system which costs $20,000,"
那永远不会发生。
A 3 ton system only rarely comes in at $30K, and a 2 ton system literally never comes in at only $20K. If those are the kinds of numbers they are using it's time to get VERY skeptical about the competence. There is a base cost they need to recover for designing the system that doesn't change with the bill of materials or the depth of the wells, and it's not cheap. Most contractors will still want to oversize the system even when handed a third party Manual-J performed by a competent engineer.
GSHP安装程序不在建筑改善业务中。虽然有些人会指出低悬挂的水果中最低的，但建筑物的性能不在他们的驾驶室中。
>“我是一个数字人。要从它中说服我，您必须向我展示计算，这东西不会在现实中节省太多能量。”
In this MN study involving in-situ monitoring of dozens of GSHP installations, the heating seasonal performance median was a COP of 3.19 (~HSPF 11) and the 75th percentile was a seasonal COP of 3.75 (HSPF 12.8). The 25th percentile was a none too impressive COP 2.88 (HSPF 9.8) See Table 7, p33 (p44 in PDF pagination):
http://mn.gov/commerce-stat/pdfs/card-residential-gound-source-heat-pump-study.pdf
So about half of the installations did no better than a typical ducted Fujitsu or Mitsubishi, and many did worse.
还有其他较旧的研究，其中有较小的系统研究，但是无论该国在哪里，这种趋势都是相似的。除非您在非常低的温度辐射中进行设计，即使拥有超出能力的系统设计师，您也不太可能击败4个季节性警察。在MA气候下，具有合格的设计师和仔细的尺寸，将3.5的警察击中3.5的警察。
只是为了逆势，是否可以将地面源的平均安装性能与空气源的特定性能进行比较吗？空气源安装程序也搞砸了。
我有一间北部的小屋，北部是6区气候，最近我进行了深入的钻井。
I can definitely say that there is no way to justify the cost of even getting one more drilled, never mind the two needed to get near the capacity to heat the place with a GSHP.
Compared to even the cost of a brand name cold climate heat pump, the extra bit of efficiency improvement, the ROI on just drilling the wells alone, never mind the equipment is many many decades.
水平场更便宜，但COP较低，因此您仍在花费相当多的钱来获得边际效率增长。
>"Just to be Contrarian, is it fair to compare the average installed performance of ground-source with the specified performance of air-source? Air-source installers mess up too."
是的，这是完全公平的。
空气源热泵系统是“罐头中的HVAC系统”，几乎不需要做正确的事情。空气在任何地方都相同 - 局部湿度和温度决定了局部平均效率。系统设计师可以将其拧紧的唯一方法确实是尺寸，或者使用完全不适当的设备设计用于更温和气候。
当然，您做的事情越多，白痴变得越有创造力，但是潜伏在该网站上的相当自学的房主可能会发现空气源热泵世界中受启发的创意天才，并避免使用它们。
相比之下，在系统设计和实施阶段，有无数方法可以搞砸地热。每个系统都是一个自定义系统，有很多鸭子可以连续获得以实现理论效率数字。
质量的电力很高，因此气体会更便宜
我认为30k可能会挖你的井。
Get realistic quotes for you client, double check them with actual installs, don't let a contractor underbid and then add on. Get references, with prices.
Geo的安装价格昂贵，您需要很多空间才能做到这一点
Get an air source heat pump number
让数字进行说话
“My client currently has oil forced hot water.”
Is the current system forced air with domestic hot water or is it an oil boiler feeding hydronic heating loop?
对于强迫空气而言，收回电力节省的井钻孔成本比较超热量小型分裂的不太可能。
For geothermal the pump usage is a total wild card. The horse power is random choice of the installer. The loops and wells are all different from one sire to the next.
沃尔塔