Thanks, Kevin, for your insight all these years! J
At your request, I’ve changed your status to standard member---anyone out there want to co-moderate this list?
I can continue doing it myself, but a 2nd moderator would help get messages approved more often.
Most of the members of this list are unmoderated, but new members and a few others require approval before the message hits the list.
I probably see an average of 3 new members and 3 messages per day that require approval.
-Myles
From: electricboats@yahoogroups.com [mailto:electricboats@yahoogroups.com] On Behalf Of Kevin Pemberton
Sent: Monday, December 31, 2012 9:57 AM
To: electricboats@yahoogroups.com
Subject: Re: [Electric Boats] Re: Think inside the box revisited
Yes Mike very slow. It is more than avoiding a 60w bulb.
Sorry Myles. I guess your right. When you build your boiler for your
steam boat, you consider surface area and heat difference to determine
the size of boiler needed to transfer the energy you need. My example
although not explained well enough, shows the lack of the heat transfer
needed to keep the temp above condensation temp or close. If the heat is
produced within the motor, less energy is needed to maintain an equal
motor temperature. This is not a small amount of energy difference
either, it is substantial. Put temp sensors in the motor housing that
run the fans when needed. My use of my inverter example shows that
although very little energy is used to keep the inverter turned on, the
time to bring the temp up in the inverter is likely 1/10 the time it
would take using the stoves fuel source. This didn't take into account
the energy difference required to bring the inverter up to operating temps.
Turn your housing fans off on your electric outboard and see how much
heat builds up and how quickly it does this. It seems that if heat was
not a standard running problem fans and fins would not be engineered
into every motor and controller. My effort with this post is to remind
that although heat is a problem while using our boats it can be a big
advantage when we store them. Only experimentation will determine if
this idea has merit in the electric boat world. But it is likely
something that could be incorporated on a boat at anchor with a useful
sized solar panel, because less energy is likely needed to do the job.
When My boat was on a mooring. When it was cold enough I kept the
lantern going. It did not keep things hot enough to stop condensate
problems but it did help A small fan in mold issue locations can keep
the condensate down. I wonder had I had electric drive at the time, if I
could have reduced chaffing on my snubbers and reduced rust in the
running gear if I had done this with motor in reverse. I will never know
because I no longer own the boat. Fact is I have not been on my
boat(canoe) in over 2 years for lack of time. Condensation will never be
an issue on such a boat, so I was only thinking others may benefit from
what I posted. The only reason I revisited the post was I felt the idea
was shut down with sarcasm before anyone could consider it. It is noted
I didn't present the idea with enough information to be thought about
seriously, so I reposted with better info. I forget that I have
researched heat transfer methods to a level that many have not, so I
left out important information.
While I am at it. Myles you may have noticed it takes me time to respond
to email. This is because I have to travel 30miles to connectivity. I
feel it is time to have you remove me as a moderator, as I don't really
fill that position. I enjoy this list as should be evident in my
continued posts, however I don't have time to weed through posts as I
did in the past. To those that would have questions about posts I have
made in the past, I would like you to feel free to email me at my
personal address, but I will be un-subscribing after this post.
Kevin Pemberton
On 12/29/2012 02:34 PM, mkriley48 wrote:
> I get it you are using waste heat from the motor to keep it dry.
> maybe a very slow 20 or so rpm would also keep the prop clean.
> The downside is it seems needlessly complicated to avoid using a 60 watt bulb.
> mike
>
>
> --- In electricboats@yahoogroups.com, "matwete@comcast.net" <matwete@...> wrote:
>> You still haven't made your case...although I could have missed something in what you've written, it seems to me that you mentioned your 60 watt motor power suggestion then abandoned explaining how this 60watts would achieve the original goals.
>>
>> From my HTC Sensation 4G on T-Mobile. The first nationwide 4G network
>>
>> ----- Reply message -----
>> From: "Kevin Pemberton" <pembertonkevin@...>
>> To: <electricboats@yahoogroups.com>
>> Subject: [Electric Boats] Think inside the box revisited
>> Date: Fri, Dec 28, 2012 7:11 am
>> Hi all,
>>
>>
>>
>> In a previous post I suggested running your motor at, well 60w( I guess
>>
>> a mistake) and it was taken wrong. Mostly it was taken wrong because I
>>
>> did a poor job of stating my case so I will try again.
>>
>>
>>
>> When I stated think inside the box Myles, returned with "while I was
>>
>> thinking outside the box". I must say I meant think inside the box. I
>>
>> have a simple 750w inverter in my rig. When I get up in the morning and
>>
>> the temp inside is below 50 deg F. the inverter will not work. I have
>>
>> two options. One is to start the fire and wait an hour for the inverter
>>
>> to warm to it's operating temp, or turn it on with a 5w load(an LED
>>
>> light rope that tells me it is working again) and wait 5 minutes to use
>>
>> it. The efficiency of the inverter is quite good and it uses slightly
>>
>> more than the LED I am plugging into it, but the temp of the mosfet tech
>>
>> inside reaches at least 15 deg above ambient in no time.
>>
>>
>>
>> On the other side of the stick the ambers inside the stove I measured at
>>
>> around 1000 deg with inferred thermometer. The stove sides measured 350.
>>
>> deg. The shield around the stove measures 175 deg. and the wall 74 deg.
>>
>> It takes the house over an hour to warm to 78 deg if it ever does
>>
>> without a fan. Another example of internal heat vs. applied heat is the
>>
>> body. internal temp 98.6 deg. Because it is so efficient it does little
>>
>> to heat the house in winter but must be considered in the summer if A/C
>>
>> is used. Although it doesn't waist much energy in comparison to work, it
>>
>> is able to maintain it's operating temp with some insulation. If placed
>>
>> next to another body on a cold night, it will help keep optimum temp in
>>
>> both bodies, but not with much air space between them.
>>
>>
>>
>> Applying heat is inherently inefficient. Pot skirts help when heating
>>
>> with applied heat on a stove, but nothing works as well as internal
>>
>> heat. For this reason when electric stoves came out, GE also offered
>>
>> inductive heating stoves. Because they limited cookware options, they
>>
>> were not to popular. Industry sometimes uses inductive heating to bend
>>
>> large tubes. In motors inductive heat is the enemy. Laminates are used
>>
>> to reduce the effect thus increasing efficiency but the losses are not
>>
>> eliminated and fans are used to control it. It is for this reason
>>
>> thinking inside the box(motor) is not such a bad Idea. As for the
>>
>> controller I just stated my case with the inverter example.
>>
>>
>>
>> I hope I better stated my case this time. All my previous statements in
>>
>> my other post still apply.
>>
>>
>>
>> Kevin Pemberton
>>
>>
>>
>> P.S. The incubator purchased at a hospital auction uses applied heat in
>>
>> the form of a 160w light. Also not a bad idea I just felt there was a
>>
>> better one.
>>
>>
>>
>> --
>>
>> Committing murder in exchange for lifestyle
>>
>> makes you a "thug" not a "Rights Activist"
>>
>
>
--
Committing murder in exchange for lifestyle
makes you a "thug" not a "Rights Activist"
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