Peri, If you like to use some of your excess heat from the top floor to remove the chill from the ground floor, you can use a ducted fan that draws air from near your top floor ceiling and exhausts that hot air into low-placed register(s) on the ground floor, so the excess heat from the top floor is added to the ground floor, removing the chill (normal behavior of cold air is to lay low since it is heavier than warm air, so you need to pump the hot air below it to mix and warm it up). Of course, I don't know how the layout of your home is and if this is feasible and sensible. Many homes use the vacant space between frame struts to transport air for heating, but it may be that you have better insulated the home or the downstairs where you want the heat is not easily reachable from where the heat is - near the top floor windows.
Cor van de Water Chief Scientist Proxim Wireless Corporation http://www.proxim.com Email: [email protected] Private: http://www.cvandewater.com Skype: cor_van_de_water XoIP: +31877841130 Tel: +1 408 383 7626 Tel: +91 (040)23117400 x203 -----Original Message----- From: EV on behalf of Peri Hartman via EV Sent: Mon 1/12/2015 6:36 AM To: Electric Vehicle Discussion List Subject: Re: [EVDL] EV Demand Response - (now Home solar) Cor, that seems like a rather small collector. Is it large enough that you got a significant benefit from it? My experience is even more basic. We have south facing windows on our upper floor (which is our main living space). Even if its 20F outside, if it gets sunny we have to open some windows to cool down. It doesn't take long to get up to 80F. The tradeoff is our downstairs doesn't get much of that heat and stays around 60F - too chilly for most people. Total space about 1500sf. Of course, cloudy days don't provide as much infrared. But those days tend to be 40-50F and don't require as much heating. The utility bill supports that this form of solar collector works. Our natural gas payments for the entire year come to about $450. Long story short, in response to Michael Ross' statement that there isn't much future for residential solar thermal, I agree only after PVs become more efficient. For the time being, though, this low hanging fruit could have huge benefits to our energy consumption. Sorry to drag on an off-topic thread. You can consider it slightly on topic, though, if you add PV generated electricty for EV charging. By offsetting your home heating with a solar collector design, you could free up funds to install more PV panels :) Peri ------ Original Message ------ From: "Cor van de Water via EV" <[email protected]> To: "Electric Vehicle Discussion List" <[email protected]> Sent: 12-Jan-15 1:02:26 AM Subject: Re: [EVDL] EV Demand Response - (now Home solar) >Solar thermal is not expensive if it is installed when the house is >built (or included when remodeled). I have heard from people in the >field that adding it to building code would not only save a lot of >energy but also save cost for home owners once the rather trivial >investment was paid off. >Another alternative - similar to EV until recently - is to do it >yourself. >I bought a second hand system ("hot top" boiler with heat exchange >coil, >a drain-back solar panel and a super simple control board for the pump) >for about $400 and installed it myself - removed some of the roof tiles >to accommodate the 6x6ft panel, drilled holes through floor and roof to >connect pipes, even added a small drain-back container since the pipes >were running in a way that otherwise would prevent drain-back. As soon >as the sun started shining in the morning, the pump would come on and >start warming the water. > >Oh, BTW, this was a "Luigjes" system in The Netherlands. The control >system consisted essentially of 2 comparators: one compared the temp in >the boiler with the temp in the panel. If the panel was warmer by a few >degrees, the pump was started. The other comparator was protection: if >the boiler temp reached max setting, the pump was stopped (and the >water >drained back). >Winter times (with freezing nights in The Netherlands) were no problem, >since there was never water in the outdoor system that could freeze. >The electronics was so simple and low-density that anybody with a >soldering iron could understands and fix it. > >This system was running the tap water through the collector (which had >copper piping) as the additional heat exchanger coil was used to allow >another source of hot water (the furnace) to be used to provide >additional heating if needed, for this purpose it measured the temp in >the top of the boiler and added heat to keep the top at high temp - >hence the name Hot Top. > >Cor van de Water >Chief Scientist >Proxim Wireless Corporation http://www.proxim.com >Email: [email protected] Private: http://www.cvandewater.info >Skype: cor_van_de_water Tel: +1 408 383 7626 > >-----Original Message----- >From: EV [mailto:[email protected]] On Behalf Of Michael Ross >via EV >Sent: Sunday, January 11, 2015 4:08 PM >To: Peri Hartman; Electric Vehicle Discussion List >Subject: Re: [EVDL] EV Demand Response - (now Home solar) > >A few years now, my business at NC State has been to test solar thermal >collectors for certification. We also offer installation training and >other CE classes for the industry: wind, PV, etc. > >To summarize, I don't there is much future for residential solar >thermal. > >It is easy and efficient to collect heat from the sun in water, most >collectors are 70% efficient, not much better, not much worse (except >if >they are total crap). The temperature of the fluid is not much use for >anything but offsetting costs of water or space heating by other means. >Simple as the collector is, the solar thermal system is far more >complicated than a PV system: you have an electrical and control >systems, >plumbing, holes in the roof, maybe a heat exchanger (for a glycol >circuit) >instead of regular hot tank for wash water, or you have a drainback >system >that empties the collector when it it is not sunny. > >There is enough complication that the cost of installation is high, and >many households simply don't need enough hot water to get any payback. >Consider my home with just two people gone half the day; $20 to >insulate >the hot water tank is a much better value than $4k or $5k to get a >collector and system installed. > >As PV gets more efficient and cost drops, it will be come much simpler >and >more cost effective to run the electric element in the hot tank. >Residential solar thermal is dying. Eventually, PV my be comparable to >the >various solar space heating options. > >There is one nice simple solar thermal idea that gets oddly little >attention and that is solar air heating collectors. We worked with a >fellow in Florida who has a nice well thought out air collector's >system. >The front glass is a standard double pane picture window. All the >materials were chosen for ready availability and cost - typical >construction materials mostly. The system couldn't be simpler - it has >a >simple bimetallic thermostat that turns the fan on above 90F and off >below. > > > > > >On Sun, Jan 11, 2015 at 3:43 PM, Peri Hartman via EV ><[email protected]> >wrote: > >> I think a combo of PV panels and solar collectors would generally be >the >> best solution, assuming you have the sun exposure. Currently PVs are >not >> very efficient. I don't have any numbers of solar collectors but I'm >> pretty sure they can beat PVs several times over. >> >> Since home heating doesn't require electricity, that could be done >more >> effectively with collectors. The EV and home appliances could be >powered >> by PVs, to the extent possible. >> >> How much reduction in fossil fuel use would depend on how your power >is >> generated and how you currently heat. In my case, home heating comes >from >> natural gas (don't have any A/C) and almost all the electricity comes >from >> hydro. Thus, the best way for me to reduce my carbon use (and reduce >> fracking) is to switch my home heating to a solar collector system. >If >> your case is, say, electricity from 50% coal and 50% nuke, where as >your >> heating is natural gas and cooling is electricity, then you may be >better >> of prioritizing the electricity generation before the heating. >> >> Either way, the amount of area required to capture kWh-equivalents is >> going to be smaller for heating than for generating electricity until >we >> have better PV technology. So, don't overlook installing collectors. >> >> Peri >> >> >> ------ Original Message ------ >> From: "Peter Eckhoff via EV" <[email protected]> >> To: "Ben Goren" <[email protected]>; "Electric Vehicle Discussion >> List" <[email protected]> >> Sent: 11-Jan-15 10:21:19 AM >> Subject: Re: [EVDL] EV Demand Response - (now Home solar) >> >> When I took a Solar Energy course way back when, my instructor said >there >>> was a "rule of thumb" for solar thermal heating. He said to take the >square >>> footage of the heated **area** and divide by 3 to produce a storage >>> **volume** estimate. At the time, fist sized rocks were used to >>>store >the >>> heat. Of course insulation, angle of the collectors to due south, >etc. >>> mattered. The idea was to pump a liquid through the collectors to >>>the >>> storage volume and then have a separate (or 3-way valve) to direct >any heat >>> from the storage volume to pipes radiating heat under the >subflooring. >>> >>> Recently, I ran a parameterized commercial solar energy program with >a >>> similar system and the system came back saying I needed a 600 gallon >tank >>> for optimum heating. In this case, a liquid is being used to store >the heat >>> instead of rocks or sand. >>> >>> While not perfect, the idea is that PV will take care of local EV >driving >>> needs and the solar thermal will address a lot of winter heating >needs. The >>> more cloud cover and colder winter temperatures, the less energy it >will >>> provide. >>> >>> On 1/10/2015 3:09 PM, Ben Goren via EV wrote: >>> >>>> On Jan 10, 2015, at 9:21 AM, tomw via EV <[email protected]> wrote: >>>> >>>> His book, Solar Hot >>>>> Water Heating, describes (among other systems) using solar hot >water >>>>> collectors to heat a 2 ft thick layer of sand which is insulated >inside >>>>> the >>>>> house foundation with a concrete slab floor on top of it, giving >over >>>>> one >>>>> hundred of metric tons of thermal mass for radiant floor heating. >Water >>>>> is >>>>> circulated through the sand with PEX tubing, starting around mid >August >>>>> to >>>>> heat it up for the winter. >>>>> >>>> Similarly, the most effective method of cooling for locations such >as >>>> Arizona where I am also uses the Earth as an heat sink...and, of >course, >>>> also similarly only really make sense for new construction. But, >>>>yes >-- >>>> done right, and you can live in arctic frigidity in the middle of >August >>>> for pennies per day. If whoever built the building had the >>>>foresight >to do >>>> things right.... >>>> >>>> But the good news is that there's insane amounts of energy >>>>available >>>> from the Sun such that simply covering a suitable fraction (and >generally a >>>> minority) of your roof space with generic PV panels results in a >>>>net >>>> surplus. And, if the grid is available to use as the equivalent of >>>>a >>>> battery, you can make an handsome profit that way if you've got >available >>>> capital to invest. Most can still make a profit, though nowhere >>>>near >so >>>> handsome and with much more capital, going off the grid entirely. >>>> >>>> b& >>>> -------------- next part -------------- >>>> A non-text attachment was scrubbed... >>>> Name: signature.asc >>>> Type: application/pgp-signature >>>> Size: 801 bytes >>>> Desc: Message signed with OpenPGP using GPGMail >>>> URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/ >>>> attachments/20150110/fd0a3ee8/attachment.pgp> >>>> _______________________________________________ >>>> UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub >>>> http://lists.evdl.org/listinfo.cgi/ev-evdl.org >>>> For EV drag racing discussion, please use NEDRA ( >>>> http://groups.yahoo.com/group/NEDRA) >>>> >>>> >>>> >>> _______________________________________________ >>> UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub >>> http://lists.evdl.org/listinfo.cgi/ev-evdl.org >>> For EV drag racing discussion, please use NEDRA >(http://groups.yahoo.com/ >>> group/NEDRA) >>> >>> >>> >> _______________________________________________ >> UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub >> http://lists.evdl.org/listinfo.cgi/ev-evdl.org >> For EV drag racing discussion, please use NEDRA >(http://groups.yahoo.com/ >> group/NEDRA) >> >> > > >-- >Put this question to yourself: should I use everyone else to attain >happiness, or should I help others gain happiness? >*Dalai Lama * > >Tell me what it is you plan to do >With your one wild and precious life? >Mary Oliver, "The summer day." > >To invent, you need a good imagination and a pile of junk. >Thomas A. Edison ><http://www.brainyquote.com/quotes/quotes/t/thomasaed125362.html> > >A public-opinion poll is no substitute for thought. >*Warren Buffet* > >Michael E. Ross >(919) 550-2430 Land >(919) 576-0824 <https://www.google.com/voice/b/0?pli=1#phones> Google >Phone >(919) 631-1451 Cell >(919) 513-0418 Desk > >[email protected] ><[email protected]> >-------------- next part -------------- >An HTML attachment was scrubbed... >URL: ><http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20150111/a00a >67ec/attachment.htm> >_______________________________________________ >UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub >http://lists.evdl.org/listinfo.cgi/ev-evdl.org >For EV drag racing discussion, please use NEDRA >(http://groups.yahoo.com/group/NEDRA) > >_______________________________________________ >UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub >http://lists.evdl.org/listinfo.cgi/ev-evdl.org >For EV drag racing discussion, please use NEDRA >(http://groups.yahoo.com/group/NEDRA) > > _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA) _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA)
