Anybody know anything about Solar or Geothermal energy?

Castenea wrote:Steam will work for as long as the proscriptions are in effect, but electric has problems with range and recharge time. Electric vehicles will be a niche item as long as ranges on full charge are under 100 mi, and recharge times are measured in hours. As a comparison most cars sold in the US today have a range of 250 to 300 mi on a full tank and can fill the tank at most service stations in under 15 min.

With Federation tech? Where you've got man-portable fusion plants that run for years and years with apparently zero maintenance after being left in a cave for a thousand years? Electric is pretty obviously the way to go, there, unless the Federation has some sort of direct-momentum-transfer field technology or something.

With-proscriptions, look at the Stanley Steamer; a steam automobile can be quiet, safe, and efficient. No need to develop IC engines. (Stirling engines also a possibility. )

Post-proscriptions, direct ammonia fuel cell electric cars would be a good first step for Safehold; ammonia is an easy to handle pumpable fuel, safer than gasoline (gaseous ammonia won't explode at STP), and you can make it from air and water using a catalytic process that's about 70% efficient. (Presumably using your first big ugly go at a fusion plant for power as the tech bootstrap gets going.) Since the fuel-cell-electric drive train is about 70% efficient as well, even without regenerative brakes, you do fine on range; drive-train total mass is less than gasoline engine drive trains.

Then you've got an electric car industry that you can swap whatever Federation highly-compressed-tank-of-electrons tech applies into once you can make those. The ammonia production can then all go to agriculture.

Castenea wrote:Steam will work for as long as the proscriptions are in effect, but electric has problems with range and recharge time. Electric vehicles will be a niche item as long as ranges on full charge are under 100 mi, and recharge times are measured in hours. As a comparison most cars sold in the US today have a range of 250 to 300 mi on a full tank and can fill the tank at most service stations in under 15 min.

Couple of assumptions here. First that battery storage in the 24th century won't be any better that it is today - not a safe assumption in my opinion. Second, have you examined what Tesla is currently producing. Range of 265 miles, recharge times of 30-45 minutes. That's today. What will 300 years of development bring?

doug941 wrote:Weird Harold Jets are still a form of IC engine, they just don't have pistons

Yes, I do know that. If I wanted to be obscure but more precise, I would be ranting against Otto Cycle Reciprocating Engines, but most people would misunderstand that, too.

Castenea wrote:I can see you actually live inside city limits. For those who do not live inside high density urban areas, personal transport is a necessity as the economics of mass transit simply do not work.

I do now, but I haven't always.

I'm old enough to remember steam locomotives as daily visitors to my home town and Diesel-Electric locomotives were a reason for a crowd to gather to ooh and aah.

I'm old enough to remember when taking the train into the big city for a shopping trip was more reliable and just as cheap as driving -- the longer the train or bus trip, the better the economics on a personal level. I remember when Greyhound competed with Trailways and both competed/collaborated with hundreds of regional bus lines.

I actually remember when Las Vegas had a railway terminal and daily Amtrak service.

Castenea wrote:Electric vehicles will be a niche item as long as ranges on full charge are under 100 mi, and recharge times are measured in hours. As a comparison most cars sold in the US today have a range of 250 to 300 mi on a full tank and can fill the tank at most service stations in under 15 min.

If there is no need to go more than 50 miles from home, why do people need 250-300 mile range; as long as they remember to plug in the car before going to bed, 100 miles is more than enough.

If there were decent bus and rail routes servicing inter-city traffic, there would be no need for personal vehicles with inter-city ranges. Inter-city travel in personal vehicles is a "luxury" that wouldn't be missed if it was never offered.

Commuters who live in Boston and work in New York are a modern (post WWII) aberration. Even so, many of that ilk use mass transit (Amtrak) instead of personal vehicles.

Historically, most people lived within walking distance from their work. Those that didn't lived within walking distance of a tram or trolley line -- once they became available -- or an omnibus route.

Weird Harold wrote:

Historically, most people lived within walking distance from their work. Those that didn't lived within walking distance of a tram or trolley line -- once they became available -- or an omnibus route.

I've read that historically, people have tended to live within 1 hours travel of their work, whether that travel is by foot, horse or vehicle.

Castenea wrote:Electric vehicles will be a niche item as long as ranges on full charge are under 100 mi, and recharge times are measured in hours.

Well the second part is pretty much a non issue already. Chargers that will take an empty battery to 80% full in about 30 minutes are widely available in the UK for instance! As the for the first part, how often does the average person do >100 mile trips anyway? The average UK commuting distance is 10 miles each way, not really sure why I'd need a car with a 100+ mile range for that! (Actually if I had a 10 mile commute, I'm not sure I'd need a car at all but that's another story!)

As a comparison most cars sold in the US today have a range of 250 to 300 mi on a full tank and can fill the tank at most service stations in under 15 min.

That's a shockingly bad tank range! The car-derived vans I drive for work will do >400 miles on a tank if driven sensibly. And that 15 minutes you quote for refuelling? Well you have to be there for all of it, apart from plugging in and disconnecting your EV will refuel itself whilst you go and do something useful with the time!

Keith_w wrote:I've read that historically, people have tended to live within 1 hours travel of their work, whether that travel is by foot, horse or vehicle.

That certainly sounds plausible, whether it is 100% correct or not.

PalmerSperry wrote:

Castenea wrote:Electric vehicles will be a niche item as long as ranges on full charge are under 100 mi, and recharge times are measured in hours.

Well the second part is pretty much a non issue already. Chargers that will take an empty battery to 80% full in about 30 minutes are widely available in the UK for instance! As the for the first part, how often does the average person do >100 mile trips anyway? The average UK commuting distance is 10 miles each way, not really sure why I'd need a car with a 100+ mile range for that! (Actually if I had a 10 mile commute, I'm not sure I'd need a car at all but that's another story!)

As a comparison most cars sold in the US today have a range of 250 to 300 mi on a full tank and can fill the tank at most service stations in under 15 min.

That's a shockingly bad tank range! The car-derived vans I drive for work will do >400 miles on a tank if driven sensibly. And that 15 minutes you quote for refuelling? Well you have to be there for all of it, apart from plugging in and disconnecting your EV will refuel itself whilst you go and do something useful with the time!

I live in South Dakota where we tend to drive a bit more, I think. We live in a small community where most of the necessities are present, but the large box stores which people patronize are 40-50 miles away in Sioux Falls. And by the time you make four or five stops, it's pretty inevitable to have 125 miles round trip. For us to visit family is about 100 miles one way. As a clergyman when I was fully employed, it was not uncommon for me to drive 100+ miles to a conference or even just making calls. When I think of places like England or any of the other countries in Western Europe, what goes through my mind is small.

Also, what plays into this is that small cars never really became overly popular with most of the population here, at least in our part of the Midwest.. People like their cars big and roomy. My work car is small car, but we have a mini-van for travel. For example we are going to a family funeral next week after Christmas which will be about a 2000 mile round trip. As long as the thing is driven conservatively, we can expect 23-24 miles per gallon.

Love of the automobile has meant that public transportation is not really very good here. If you live near a large metro area, flying is not too bad, but from small airport to small airport, it gets very expensive.

So, I guess I'm as bad as most people out here with what I will refer to as a Midwest mentality. I like my car. I like coming and going as I wish, stopping where I want to and the notion of a bus or plane really doesn't seriously enter my thinking. For what it's worth, that's the way it is...

Don

Castenea wrote:Electric vehicles will be a niche item as long as ranges on full charge are under 100 mi, and recharge times are measured in hours.

PalmerSperry wrote:Well the second part is pretty much a non issue already. Chargers that will take an empty battery to 80% full in about 30 minutes are widely available in the UK for instance! As the for the first part, how often does the average person do >100 mile trips anyway? The average UK commuting distance is 10 miles each way, not really sure why I'd need a car with a 100+ mile range for that! (Actually if I had a 10 mile commute, I'm not sure I'd need a car at all but that's another story!)

As a comparison most cars sold in the US today have a range of 250 to 300 mi on a full tank and can fill the tank at most service stations in under 15 min.

That's a shockingly bad tank range! The car-derived vans I drive for work will do >400 miles on a tank if driven sensibly. And that 15 minutes you quote for refuelling? Well you have to be there for all of it, apart from plugging in and disconnecting your EV will refuel itself whilst you go and do something useful with the time!

n7axw wrote:I live in South Dakota where we tend to drive a bit more, I think. We live in a small community where most of the necessities are present, but the large box stores which people patronize are 40-50 miles away in Sioux Falls. And by the time you make four or five stops, it's pretty inevitable to have 125 miles round trip. For us to visit family is about 100 miles one way. As a clergyman when I was fully employed, it was not uncommon for me to drive 100+ miles to a conference or even just making calls. When I think of places like England or any of the other countries in Western Europe, what goes through my mind is small.

Also, what plays into this is that small cars never really became overly popular with most of the population here, at least in our part of the Midwest.. People like their cars big and roomy. My work car is small car, but we have a mini-van for travel. For example we are going to a family funeral next week after Christmas which will be about a 2000 mile round trip. As long as the thing is driven conservatively, we can expect 23-24 miles per gallon.

Love of the automobile has meant that public transportation is not really very good here. If you live near a large metro area, flying is not too bad, but from small airport to small airport, it gets very expensive.

So, I guess I'm as bad as most people out here with what I will refer to as a Midwest mentality. I like my car. I like coming and going as I wish, stopping where I want to and the notion of a bus or plane really doesn't seriously enter my thinking. For what it's worth, that's the way it is...

Don

And 175 years ago, before the advent of the railroad and automobile, you would either have had a small town with a general store close at hand, or you would have been completely self sufficient, which is the situation in Safehold. I suspect that Merlin will put the brakes on personal transportation to avoid this problem until it is solvable with a solution better than the IC engine, just to avoid the problems that Earth had with it.

Graydon wrote:
Post-proscriptions, direct ammonia fuel cell electric cars would be a good first step for Safehold; ammonia is an easy to handle pumpable fuel, safer than gasoline (gaseous ammonia won't explode at STP), and you can make it from air and water using a catalytic process that's about 70% efficient.

Of course the downside of ammonia gas is that a good lung full will kill you stone dead - its highly toxic because is turns water in your lungs into ammonium hydroxide - think a lung full of caustic soda. Diesel is much safer - it doesn't explode and you can handle a lung full of fumes with no major side effects beyond a bad hangover. You can also run fuel cells on diesel (I've worked on self reforming high temperature fuel cells and know it works (but still needs work for commercial applications)). Efficiency is around 55% on diesel - 60% theoretical and 5% in thermal losses (as heating the fuel cells to 900C takes power).

AirTech wrote:

Graydon wrote:Post-proscriptions, direct ammonia fuel cell electric cars would be a good first step for Safehold; ammonia is an easy to handle pumpable fuel, safer than gasoline (gaseous ammonia won't explode at STP), and you can make it from air and water using a catalytic process that's about 70% efficient.

Of course the downside of ammonia gas is that a good lung full will kill you stone dead - its highly toxic because is turns water in your lungs into ammonium hydroxide - think a lung full of caustic soda. Diesel is much safer - it doesn't explode and you can handle a lung full of fumes with no major side effects beyond a bad hangover. You can also run fuel cells on diesel (I've worked on self reforming high temperature fuel cells and know it works (but still needs work for commercial applications)). Efficiency is around 55% on diesel - 60% theoretical and 5% in thermal losses (as heating the fuel cells to 900C takes power).

Threshold of detection is three orders of magnitude lower than the toxic threshold for ammonia, so it's very easy to be aware of a leak. And the gas is lighter than air, so it goes up and away.

It's certainly possible to run fuel cells on diesel but this doesn't get you away from the messing-up-the-atmosphere-with-carbon problem. Safehold might not care (or they might; it is, after all, a thousand-year-old artificial environment and plausibly kinda sensitive to being perturbed.) And of course diesel in combustion engines contributes to substantial excess deaths through air pollution, it's just hard to separate out the specifically diesel numbers from the overall numbers.