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valhalla360 · 19-11-2019, 03:57

Quote:

Originally Posted by NorthernMac

How do outboards do running 8+ hrs a day? I’d think a outboard gas engine would be more prone to issues than a simple inboard diesel with no electronics for the most part?

That's how we used our 25hp EFI outboard...seemed fine with it. Outboards are pretty durable.

Then again ICE like to be run continuously vs starting and stopping before they get up to temperature.

valhalla360 · 19-11-2019, 04:07

Quote:

Originally Posted by DeepFrz

However, I will argue that electric motors can be much more efficient than in previous years due to research and I argue that LFP batteries are much more efficient than LA batteries. I do see that the producers of LA batteries are spending more on research so that even they are more efficient than they were a few years ago.
.

Electric motors have been able to hit well above the 90% range for efficiency for many years (decades even)...unless you develop a Perpetual Motion Machine...there isn't much room for improvement.

Sure LFP are better than LA...but LFP isn't new tech either. There has been economy of scale improvements but those have mostly been achieved and not lithium supply may cause the price to tip the opposite direction.

Lake-Effect · 19-11-2019, 04:18

Quote:

Originally Posted by Reefmagnet

That's not how code compliant wiring is done.

I was responding to the suggestion that home charging of EVs would stress the grid and home wiring.

I'm familiar with wiring to code, but the current code that I know doesn't take into account the times of use and other means of load management. As EVs become more common, the electrical codes will be revised to address this.

valhalla360 · 19-11-2019, 04:18

Quote:

Originally Posted by KTP

If a monohull were designed from the ground up to be electric inboard it could be done fairly well.

The battery bank could be encapsulated into the bolt on keel which solves problems with cooling and fire hazard, plus the weight is the most useful there. You would still need some lead in the keel but you could probably get something like a 200kWh car type battery pack in the space traditionally meant for keel mass and diesel fuel tank.

With 200kWh, you could motor for 10 hours at 7 knots or 20 hours at 6 knots, several days at 5 knots, easily enough range for the way most people use their marina kept sailboats.

10 year lifespan on the battery but near zero maintenance during the 10 years.

Last I heard an 80kwh tesla battery bank is about $15,000. Assuming a similar price per kwh, you are talking about somewhere on the order of $35,000 for the battery bank.

Of course, your boat won't have the economy of scale advantages, so it could easily top $50-75k for an installed battery keel. That's a lot of fuel and diesel maintenance on a 40ft sailboat to make up the cost difference.

valhalla360 · 19-11-2019, 04:25

Quote:

Originally Posted by roland stockham

It would not be good to get into an argument about who has the best data and I am never sure how reliable statistic published on the internet are. I got my numbers from a set of graphs published on Youtube and now you have challenged them I realise I was guilty of passing them on without fully verifying the sources of the data.
So here are some numbers that I grabbed quickly from WIKI for top performers in renewable electricity generation from all countries.

Albainia, Iceland, Paraguay, 100%
Namibia, Costa Rica, Tajikistan, Norway, Uruguay, Zambia, Etiopia, Kenya, 90 - 100%
....

The first world countries (Iceland & Norway) have huge Traditional renewable electricity sources (hydro & geothermal) relative to the population based demand. When the electric grids were first developed, they were almost 100% renewable but then people away from large dam projects wanted electricity and fossil fuel based plants were developed.

Most of the others listed have minimal demand and underdeveloped and/or negligible power grids. If you are talking about powering a village with no grid access, a solar/battery system that can provide 5kwh per month per home is a huge improvement and on a per house basis, pretty cheap...by western standards...where it fails by western standards is it provides nothing close to the number of kwh westerners expect to be available. Scale it up and provide the reliability expected and suddenly, it's not so cheap.

So yes, we can go heavy into renewables but only if you expect people to drop way back on expectations.

Chotu · 19-11-2019, 04:36

Quote:

Originally Posted by valhalla360

That's how we used our 25hp EFI outboard...seemed fine with it. Outboards are pretty durable.

Then again ICE like to be run continuously vs starting and stopping before they get up to temperature.

Same experience here with 30hp EFI outboards. So far, 4 years of complete reliability covering a couple thousand nautical miles. No oil changes either, plus they fog and store themselves properly when not in use.

Like most things on a boat, the more they are used the better. Sitting is the enemy of all but sails and rigging.

waterman46 · 19-11-2019, 14:18

Quote:

Originally Posted by Sailmonkey

What I see as a looming problem is the current electrical grid.

No-one likes to address this weakpoint. Sections of the US already experience rolling blackouts during times of peak demand.

For the foreseeable future electric cars etc are fine as a novelty, but in order to mainstream them, large changes will need to be made in the power generation and distribution grids globally.

Power for cars and trucks is only one part of the problem. There is an even more pressing need for vastly increased power transmission capability. If we are to go solar for most of our daytime power demand, we need to put huge solar generation plants in the Southwest (CA, AZ, NM) and we need to transmit this energy to the frozen north.

It is amazing that nobody seems to remember that the sun does not shine at night! Just when household demand is high in the evening, especially in the North in winter. Huge batteries? I don't think so. Design of homes to store heat in the floors and walls during the daytime, yes definitely. Wind? Good luck with that, maybe 15% at most, and quite variable. Hydroelectric? The eco-nuts won't let us dam more rivers. Other than fossil fuels, only nuclear power can fill in these energy gaps. The French seem to be doing just fine with it, but only millennia of time will reveal the full effects.

Reefmagnet · 19-11-2019, 14:28

Quote:

Originally Posted by waterman46

Power for cars and trucks is only one part of the problem. There is an even more pressing need for vastly increased power transmission capability. If we are to go solar for most of our daytime power demand, we need to put huge solar generation plants in the Southwest (CA, AZ, NM) and we need to transmit this energy to the frozen north.

It is amazing that nobody seems to remember that the sun does not shine at night! Just when household demand is high in the evening, especially in the North in winter. Huge batteries? I don't think so. Design of homes to store heat in the floors and walls during the daytime, yes definitely. Wind? Good luck with that, maybe 15% at most, and quite variable. Hydroelectric? The eco-nuts won't let us dam more rivers. Other than fossil fuels, only nuclear power can fill in these energy gaps. The French seem to be doing just fine with it, but only millennia of time will reveal the full effects.

Given enough solar, wind and hydro generation capacity, it is theoretically possible to have 24/7 power available entirely from renewables. It would be a massive engineering undertaking to build though.

Lake-Effect · 19-11-2019, 14:28

Quote:

Originally Posted by waterman46

Power for cars and trucks is only one part of the problem. There is an even more pressing need for vastly increased power transmission capability.

If we are to go solar for most of our daytime power demand, we need to put huge solar generation plants in the Southwest (CA, AZ, NM) and we need to transmit this energy to the frozen north.

I think it's more the opposite - conservation measures have slowed down the growth-rate of electrical demand, and if new and different generators are better distributed, there's less need to transmit from distant megaplants to population centers.

And no, I don't think there's any realistic expectation that the north would get power from solar megafarms in the southwest.

Reefmagnet · 19-11-2019, 14:33

Quote:

Originally Posted by Lake-Effect

I think it's more the opposite - conservation measures have slowed down the growth-rate of electrical demand, and if new and different generators are better distributed, there's less need to transmit from distant megaplants to population centers.

And no, I don't think there's any realistic expectation that the north would get power from solar megafarms in the southwest.

No way has electrical demand declined. That's just crazy talk. EV's are just going to add to the demand as more and more are brought online.

**newhaul** · 19-11-2019, 15:45

Quote:

Originally Posted by Reefmagnet

No way has electrical demand declined. That's just crazy talk. EV's are just going to add to the demand as more and more are brought online.

LE didn't say it had declined he said the broth rate is lower as in example instead of growing at 10% per year its growing at 9.5% per year. ( those are not real numbers they are just for illustrative purpose)

Lake-Effect · 19-11-2019, 15:46

Quote:

Originally Posted by Reefmagnet

No way has electrical demand declined. That's just crazy talk.

Yes it is. That's why I didn't say that "electrical demand declined". I said the rate of increase has slowed down.

[source]

Or as newhaul stated - broth rate.

**newhaul** · 19-11-2019, 15:46

Quote:

Originally Posted by Reefmagnet

No way has electrical demand declined. That's just crazy talk. EV's are just going to add to the demand as more and more are brought online.

all ev does is change where the co2 and the pollutants are produced. It definitely doesn't actually reduce it .

Lake-Effect · 19-11-2019, 16:01

Quote:

Originally Posted by newhaul

all ev does is change where the co2 and the pollutants are produced. It definitely doesn't actually reduce it .

Electrical generation at scale is more efficient and cleaner than producing, distributing and burning gasoline. Electricity can come from non-CO2-generating sources. Also, EVs are more efficient (eg regenerative braking).

So, yes, EVs reduce the production of pollutants and CO2.