Words and Images by: Collyn Rivers N8054

It is prudent to be wary of advertorial/marketing claims: not because of untruths, but because that claimed is often only achievable in improbable circumstances. This is usually revealed in published vendor data – and may ensure legal immunity, but often in terms that, without some physics (and a nose for bovine ordure) may not be understood.

One, relating to an (MPPT) solar regulator, claimed ‘up to 300%’ gain. The unit had done that claimed: but in the Arctic Circle, and of nominally 100 watt solar modules that produced 3.0 watts rather than 1.0 watt for a few hours. The local importer misunderstood the data and stated that, via this unit, 100 watt modules would produce up to 300 watts.

The manufacturer had never intended that data (whilst correct) to be extrapolated to suggest such gain was generally achievable. This technology cannot produce ‘gain’: it recovers 10%-15% of the 20% or more energy otherwise lost through power mismatch etc. Most vendors truthfully claim ‘up to 30%’ but do not reveal that is for about half an hour around sunrise and dusk such that a 100 watt module may produce about 10 watts instead of 7.0 watts or so.

Small Wind Generators

Another example is small wind generators, effective in small boats, but not in urban and RV use. A typical 1.0 metre diameter unit probably will produce the 300-400 watts typically claimed – at a constant wind in excess of 20 metres a second (m/s) on top of a 10 metre tower. Whilst technically correct, that 20 m/s misleads as few people have any realistic concept of constant wind strength. Nor that multiplying it by 3.6 results in kilometres/hour.

Promotion may suggest useful output at 25 km/h, but not reveal that even a  constant 15 km/h is above the yearly average of the windiest coastal areas of Australia year-round, let alone inland. It is rare to find any small wind generator that produces more than 0.5 amp at a battery charging 14 or so volts at 15 km/h.

Few buyers and marketers understand wind power’s fundamental limitations. The output is proportional to the square of the propeller’s diameter (regardless of blade number), and the cube of the steady wind speed.

Power thus increases eight times as wind speed doubles – and vice versa, i.e. virtually nothing most of the time.

Rated output is typically just prior to a unit’s self destruction. Consider this: twenty metres/second is about 70 km/h: Tropical Cyclone Category 1 has a mean wind speed of 63-78 km/h. (Source - the Australian Bureau of Meteorology.)

Much of the above is disclosed in the products’ specifications. But they may as well be in Old Norse for readers without technical understanding. Further, that maximum rating may be qualified by a term such as ‘with voltage limiter disabled’ (an actual example). That is  marketing-speke for ‘with its brake off, one second before it self-destructed’.

On-Road Weight

Another concern relates to Tare Mass (the mass of a trailer such as a fifth wheel caravan when not carrying any load, but ready for service). It is typically quoted by its maker as that of the basic product. ‘Optional extras’ specified by the buyer, are often (and usually unrevealed to  the buyer) supplied and installed by the end dealer – even though specified on the original order. These may include heavy air conditioners, awnings, extra batteries, inverters, generators etc. All form part of the Tare Mass that must be updated and revealed accordingly.

Also quoted is Aggregate Trailer Mass: i.e. Tare Mass plus allowance (often 250- 350 kg) for personal effects and the tow ball load imposed on the towing vehicle.

As ATM is the unit’s maximum legal onroad weight, all such options form part of the Tare Mass. There are anecdotal claims that this is not always revealed. As a result that personal effects allowance may barely exist.

The situation is different for RVs based on commercial delivery vans etc, but here again owners allege ex showroom weight may exceed that claimed.

Fuel ‘Savers’

It is still common to find claims made for ‘fuel savers’ – and ‘officially certified’ by the official classification ECE-R83. But what is rarely if ever revealed is that relates to exhaust emissions - fuel consumption is not measured.

A few claims are fraudulent. A globally sold ‘fuel pill’ later proved to have zero effect. But the ‘product’ was not a fuel saver. It was costly franchises, buyers of which sold sub franchises, who then sold sub-sub franchises and so on. Whether the pill worked was irrelevant. All needed was claims it did, via massive advertising and advertorial, phony ‘tests’ and ‘testimonials’ (from the franchisees). The $150 million Ponzi scheme resulted in its founder being jailed.

Many franchisees convinced themselves the pill worked. Also were testimonials from pill buyers – sometimes of extraordinary increases in power despite up to 40% fuel saving. The claims were  so blatantly absurd that (not disclosable for legal reasons) The Wanderer rejected related and associated advertising.

Some may well have experienced marginally lower fuel usage, but such consumption is difficult to measure within plus/minus 5%. Temperature and barometric changes affect the fuel that can be held by the tank. Fuel pumps are neither 100% accurate nor 100% repeatable. Fuel station forecourts are not always level. Minor changes in driving patterns affect consumption.

But most would have experienced the well known placebo effect: that being told something works can prove as effective as something that really does work. A useless ‘fuel economiser’ may well cause a buyer to be aware of fuel wasting habits and change driving pattern accordingly. In an experiment (at GM Research), half the test fleet’s drivers were told that their cars had been ‘tuned for economy’, but had not. Yet those drivers still recorded statistically significant reductions comparable to the cars that had been so tuned.

Another example is forum posts relating to a (particular type) battery. Some claim more usable energy than demonstrably available to charge it. But doing that requires a perpetual motion machine with a power take-off.

Journalists can unintentionally mislead. Newspapers may report a leader’s popularity difference to be (say) four points in 50. Yet sampling may be such that accuracy can be plus or minus 3.5% for each. The ‘poll’ is meaningless.

Some vendors take advantage of gullible buyers: e.g. selling plain water at vast prices as ‘Genuine Placebos’, and describing them totally accurately – as ‘proven to work’.

Cognitive Dissonance

Much is explained by social psychologist Leon Festinger’s ‘Theory of Cognitive Dissonance’: in effect the human motivational need to reconcile and justify contradictory ideas, attitudes, beliefs and actions - and doing so by self-justifications in often curious ways. ‘That Lo-Blow filter does so work! I spent $250 on it and I’m no fool’.

It partially explains weird justifications when an apocalypse fails to manifest: e.g. ‘we’ve been so good/so bad that we’ve been given another six months to rejoice, (or repent).’

It assists to explain how a salesperson can truly ‘believe’ that an XYZ motorhome is the very best – despite believing the exact opposite a week before - whilst flogging ZYXs.

Another, that someone with an extreme belief can more readily switch to virtually the opposite, than to a neutral position.

Collyn Rivers

Category: Technology
Written: Sat 01 June 2013
Printed: June, 2013
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