Heat pump plus comprehensive plan
 

Attached is a sketch of a comprehensive plan for space and water heating for both my current house and another smaller house I'm in the early stages of constructing. In our house we have the in-floor radiant system and the PV solar array already. I am preparing to install the source field and heat pump over the next year or two. All of the shown components will also be put in the new construction although the PV solar will be somewhat smaller since it is to be a smaller house at 1200 SF.

I have spent a good deal of time trying to understand how to integrate these systems to achieve as close to an energy zero house as possible. The missing feature in the sketch, of course, is the means of monitoring and controlling the system. I want to employ many, many sensors, so I can learn what's happening, for example, in the ground where the source loop is planted. That phase will come eventually, but for now I feel happy to have simply conceived of the project as a whole instead of many, separate parts I've got to link together.

I'm putting the sketch up for comment and criticism because I've come to realize that this site is populated by lots of folks who know their business and are creative thinkers. I'll do my best to respond to questions. The PV array can be found on another thread titled "DIM 5500 w PV Array," and a short video of it can be found on YouTube at "TrackingQT1." Conversations about our radiant heating system can be found on other threads. Thanks in advance for your advice.

Michael Moreland
Mendocino, CA

A simple way to control and monitor this system would be to use an Arduino. You can get control boards starting at $20 at radio shack, and they are scalable. There are plenty of sensors, interfaces, displays, and doodads to do what you are trying to accomplish. They are easy to program and debug, and lots of premade code and library files abound on the internet. You could put one together for your proposed setup for well under $100.

For a system that elaborate you might want to consider the Raspberry Pi. It's just a little more expensive than an official Arduino but far more capable. The added cost is basically nothing compared to the total cost of the system and having more CPU and memory will let it run your stuff better.

I'm working on a "simple" hybrid air conditioner and I'm already looking at a 533MHz ARM platform (from a broken Kindle 3) to run it. (It's too bad that my old 200MHz Jessica Simpson development board doesn't have I2C or SPI or I would have used that. I messed something up a long time ago so it no longer boots, but that's another story...) My design is going to have wireless sensors to detect the water heater temperature, which turns out to be quite involved as far as all the encoding and stuff is concerned. While I'm sure my friend Tiffany Yep could make something that would work very well, she'll insist on using an expensive FPGA rather than a cheap processor. Having such a powerful CPU would help loads with simplifying the receiver circuits.

Having a look at the schematic, I have found that it is best to introduce the cold water to the bottom of a solar tank. Take out the drain, put in a brass tee and use the extra port. Those dip tubes cause mixing and take away the stratification that is needed to get the most of the solar. Just a thought.

It's really great that you have put this drawing up as a focal point of this discussion. I really hope other EcoRenovators follow your clarifying example. as far as I'm concerned, you have just raised the bar for all of us in a very good way.


Your drawing is an excellent idea, but some other information that will prove to be just as helpful will be:

• Your HDD & CDD information. Knowing what the Heating and Cooling Degree Days are at your site or as close as possible. HDD & CDD can be gotten from THIS website. Since EcoRenovator draws an audience of international viewers, many of whom have superior understanding of these problems and solutions, you should run the calculations separately for Imperial units an also Metric units. It does not work to run the calcs for Imperial and the convert to metric... you need to run them separately.
  
• Any microclimate information that will cause serious deviation from HDD & CDD. Are you in a specific location where the wind blows continuously? This could have a big impact on how you should best proceed.
  
• Your heating load and cooling load information. You should not proceed very far in your design until you actually know what your design needs are. How can you dig a loop field if you don't know how much heat you will require? You can find a free calculator HERE that will do a very good job of giving you that information. You should also go over your home energy bills and sum them up as a total (BTU/hr and kW-h) per month, to use as a double check.
  
• The results of your blower door test. You really should do this since the greatest source of heat loss is due to infiltration.
  
• The current level of insulation in your home. Unless you have already installed very robust insulation, money spent on insulation will bring you more benefit than money spent on alternative energy.

If you're serious about zero energy, then you will have to balance out all your minuses (this means ALL your energy losses) with all your pluses (this means ALL your energy gains). So you need to know what your energy losses actually are, and also all of your energy gains, in a completely accounted for and quantified way.


michael, if you actually want people to help you, you should give them a link to the beginning of that thread. You should edit that link into your first post in this thread.


...same thing here. If you really want people to give you useful advice, link to the video you are referring to. I'm pretty sure that less than 20% of the people who have read your initial post even bothered to seek out and watch your video.


"Other threads"? What other threads? Is it late at night and you are falling asleep? Wake up michael! Leave some links to those posts.


If you are serious about getting advice, you need to be serious about supplying relevant information upon which to base that advice.




Please understand, I am trying to help your project succeed.

Best,

-AC_Hacker