Yes one thing that needs to be stressed amongst our politicans is that NO further development of the rail network (or even increase in the frequency of trains) can happen till after the CBD tunnel is constructed…

It is simply the most important transport project in Auckland and Joyce will only fund it after we’ve tarmaced the entire country…

Well – TECHNICALLY an empty plane will use slightly less fuel than a full one. The additional CO2 from the mass of the passenger is negligible compared to the fuel for the mass of the plane. This is due to the induced drag required to lift the additional mass. The argument can also be made that the airlines would not long fly empty planes about and the schedule would be cut back if there were no demand.

Zeppelins are better than planes in this regard (more like ships). There is no induced drag component. They are however, slower.

I know I have claimed that Zeppelins are better before, but now I want to try to quantify this because I am not THAT sure.

However, people who do offset their flights tend to think in terms of the total picture, and since the Airlines do not do offsets for the mass of the plane less passengers and cargo, adding this to their overheads and adjusting ticket prices accordingly (which would be the most correct way to arrange this), so that the additional Carbon offset for the passenger was due to the passenger and their luggage mass. It is reasonable for us to take responsibility for both the market demand we represent (leading to the existence of the flight) and the carbon we ourselves contribute by being on it.

For maximum advantage a Zep has to be long, large and slow. The same characteristics that make ships efficient make Zeps efficient.

A bit longer winded comparison. Lets say a LOT longer winded

Merry Christmas.

Overall one might persuade a Zep to an maximum velocity of 150-200 kph (dependent on the prevailing wind and the Zep does not have the flexibility of altitude that an aircraft has, as 3000 meters or so would be its best loaded effort). At 135 kph cruise you get to Sydney 2150 kilometers away, in about 18 hours and it took 2940 KW to achieve this speed back in the 1930′s using 16 cylinder diesels. Current diesels get 155-160 grams of fuel per KWH about a 10% improvement. Assuming similar aerodynamics and mass this would mean that a Zep would take 470.4 KG of fuel per hour of flight or about 8,500 kg of fuel to go to Sydney. At 0.85 kg/liter that’s just exactly 10000 liters. Which makes it about 4.65 liters per km or 8.6 liters per nm.

At full load the generally documented consumption Jumbo Jets is about 17 liters of fuel per nautical mile. Nautical miles are convenient for navigation (due to the relationship to degrees of lat) , not comparison:-), equivalent to 1.852 kilometers… so call it 9.182 liters per kilometer, by all means round it to 9 liters…

That isn’t actually bad on a per-person basis… compare it to cars… and the reason it isn’t makes sense in terms of the packing of the passengers (loaded buses are more efficient than cars on a per-person basis), which is in turn, only really feasible because the flight is quick enough.

Hydrogen vs Helium:
http://www.time.com/time/magazine/article/0,9171,786149-2,00.html

The Jumbo can haul a max of 134000 kg. They are big at 76 meters long yet the Graf Zeppelin was 3 times longer at 244m (only 41 meters in diameter and not the optimum aerodynamic shape).

So, the Zep is at least 2 times as efficient as the Jumbo for the trip, can stop and hover, can fly slower for better efficiency. and while the largest zeps only had a payload of 10-12000 kg (40 passengers and 40 crew) from a total mass of 232500kg, that was with 1930′s structural techniques and aerodynamics, and the limiting size of the construction shed at Friedrichshaven.

The Zeppelin NT which is more modern tech, has a payload of 1900 kg out of 8040 using Helium (10% penalty). IF that scaled up to the volume of its Grandparent it would carry 45000 kg. I think it would not precisely scale and take 10% for comparison. Call it 40,000 kg. The max Take-Off weight of a 747 is 442000 kg. This would be require roughly double the gas volume of the big Zep to get equivalent lift. The nice thing about the Zeps is that it does not need as much more power to drive the bigger airship.

http://www.zeppelinflug.de/seiten/E/zeppnt_techn.htm

The questions around this are interesting to me.

So – Does any of it make SENSE?

I think yes… but not as much as before and the business case is damaged by the weather sensitivities.

Initially I would expect it to be useful for things that take air-freight now. Flights would require sleeping accommodation for anything longer than Auckland-Sydney. That cuts into mass a bit, but the size limitations of the usual airliner don’t stop you from making such arrangements. The food requirements for the humans embarked are more serious impediments.

For NZ, Auckland to Sydney or Brisbane would be accessible and in overnight trips, would be not particularly painful. Much would depend on the scale of whatever was built. For smaller Zeps the lower capacity would mean for equivalent mass you’d need more trips. This would cut against the efficiency argument. Dropping back to 80 KPH from 120 will double the efficiency of any Zep… but makes the trip a full 27 hours. For Cargo the extra 10 hours isn’t that significant. For people it is. There’s a lot of surface for lightweight solar collection. Not energy dense, but perfectly good – in the daytime.

The Zeppelin NT might also be good for fair weather maritime patrols. The ability to hover and drift makes it useful for surveillance, but no Zeppelin is a foul weather flier.

Larger Zeps would be able to beat on the Jumbos but they would be only 4 times as fast as a big surface ship… and the big ships are damned efficient too.

Hope this helps someone somewhere. I certainly am tired of it.

respectfully
BJ

sweetdisorder, we needed 1,035,000 people at Copenhagen. People have to come together for some things and this is one of them. Because a conference fails does not mean we shouldn’t try. It means we aren’t trying hard enough.

SPC – It actually seems reasonably straightforward to work out that both scheduled and private flights contribute to emissions.

If people decide to fly less on scheduled flights, there will be a reduction in demand, a reduction in flights, and a reduction in emissions. In the news today (http://www.stuff.co.nz/business/industries/3188424/Air-NZ-returns-to-Australian-market) air NZ cites a 3.7 per cent fall in demand and a 10.2 per cent cut in capacity. They don’t state what emissions reductions this resulted in, but it is a reasonable assumption it will be significant, in the order of say 5-11%

sweetdisorder – Criticising green politicians for their emissions for traveling to Copenhagen is an easy cheap shot. Yes, their travel resulted in emissions and contributed to global warming. However, the travel of “business as usual” advocates and their stooges to Copenhagen will result in far more emissions.

If we had more green leadership representing countries, we could get past this unhelpful political bickering and actually start the work that is urgently needed.

@Owen McShane – “You might begin by asking the obvious first question: what is the problem you are trying to solve?
Rather than what is the solution you are trying to justify”…

Funny, I was was thinking the same thing myself…

Do we want to move people and freight for the lowest overall cost [including the off Balance sheet costs, and they are real costs!]…

or are you just trying to justify a “Roads of National Significance” policy Because it’s a Policy for some other reason than it making Business sense? – Where is the report on Road vs Rail or other sustainable modes option?

KiwiRail reports to Messrs Joyce and Guy directly, not via LTNZ… there is not independent or logical analysis happening here…

This is National delivering on some policy that they did not campain on, dreamed up in a back room… and they are not making the business case publicly available.

This graphic (http://maps.grida.no/go/graphic/world-greenhouse-gas-emissions-by-sector) shows we need to work most on emissions from: Deforestation (18%), Road transport (10%), Residential buildings (10%), Agricultural soils (6%), Commercial buildings (5%) and livestock emission (5%).

Air travel is below 2%.

For NZ, I guess we need to get our own forests in order, then look at our imports and what else we can do to sustain forests worldwide.

For road transport, we need to be encouraging public transport and other transport modes especially for places like Auckland. We need to put long distance travel and freight onto electrified trains and ships.

We need to increase the energy efficiency of our housing and commercial buildings.

We need to do research on ways to reduce agricultural emissions, and implement those we already know about.

This is all pretty familiar stuff.

Air travel is down the list in terms of the biggest emitters, but personally I think we need to scale it back by a large degree. Switch to fewer sea and land transport journeys for holiday trips, and the same with more video conferencing for business travel. Also more localised enterprises so we don’t need to travel.

Evidence, Owen?

Scan and post the back of your your envelope please,

Actually the quickest back of the envelope calculation shows that a rail link to the airport is a gross misallocation of resources of every kind and certainly does nothing to reduce the carbon footprint of anything..
You might begin by asking the obvious first question: what is the problem you are trying to solve?
Rather than what is the solution you are trying to justify