Air or steam ejectors seem to offer a cheap and simple alternative to a vacuum pump, but be careful: they're one example of how the UK's Climate Change levy changes economic balances
Politicians with a sense of humour? Expecting business to pay for saving the planet is one thing; but a Government that chooses April 1st to slap a 10% increase on industry's electricity bills, is definitely whimsical! Businesses that haven't heard about the Climate Change Levy 1 (CCL) - are in for a rude awakening when the second quarter's electricity bills arrive.
Billed as industry's energy tax, the levy is expected to raise some £1billion in its first full year (2001/02).
The CCL will be introduced from 1st April 2001, as a major plank in the Government's overall Draft Climate Change Programme, aimed at reducing greenhouse gas emissions.
The levy rate has been set at 0.43pence per kW/h for electricity - effectively a 10% increase on the current (general) industrial tariff 2 of 4.10 pence per kW/h.
For larger users of vacuum and compressed air, say in the print and process industries, the increase may be large enough to bring about a step-change in their attitudes to running costs.
Certainly, anybody considering the installation of vacuum ejectors should be made aware of the financial impact of the CCL on their decision.
Companies that have not subjected running costs them to the same scrutiny as capital investments, will feel the effects of the CCL most keenly.
For example, air or steam ejectors seem to offer a cheap and simple alternative to a vacuum pump, particularly those businesses which install venturi devices* a few at a time.
What isn't appreciated is the substantial compressed air consumption required by vacuum ejectors.
A medium-capacity air ejector needs 4000 l/min of compressed air at 7bar: an output that requires 28.6kW of motive power.
If the vacuum ejector is used in a two-shift operation running for, say, 4000 hours per annum then the effect of the Climate Change levy will add some £470.00 to the annual running costs of that one device.
A rotary vane vacuum pump of similar capacity only requires a 7.5kW motor. In other words, it will use about one quarter of the power required by the vacuum air ejector.
Based on the same 4000 hours per annum operation, the CCL would only add £123.00 p.a.
in additional electricity charges.
.
*Vacuum air or steam ejectors are simple venturi devices with no moving parts.
Essentially, they comprise a jet nozzle that is aligned with a diffuser. Compressed air is forced through the nozzle into the diffuser, thus entraining the gas in the inlet chamber and creating a vacuum.
The sensible option from a cost viewpoint, would be to opt for the vacuum pump in the first place, as is independently acknowledged by the DETR 3.
Arguably, venturi devices are simple to maintain (compared with a rotary vane design), but they are not maintenance-free, nor are the compressors that power them. However, any marginal benefits in maintenance costs for vacuum ejectors are heavily outweighed by their additional running costs.
In the above examples, the Rietschle vacuum pump offers annual savings in electricity charges, of œ3,460.00.
From April, users of vacuum and compressed air will no longer be able to ignore running costs.
With that in mind, Rietschle has developed an economic evaluation spreadsheet programme 4, which analyses the capital and operating costs of vacuum pumps vs.
venturi devices.
The programme will be of considerable assistance to companies in their choice of vacuum systems, and a Rietschle engineer carries out the analysis - at no cost.
Industrialists of course, can always avoid the new energy tax, by covering the factory roof with solar panels and wind turbines.
The Government regards these energy sources as environmentally cuddly, and they are exempt from the CCL.
Alternatively, they could become registered charities; a term some chief executives might say, was a recognisable description of their business in the first place! On a more serious note, industry should also be aware of the Enhanced Capital Allowances (ECA) scheme 5 which the Government is planning to introduce for companies prepared to invest in technology that is more energy-efficient.
Under the scheme, 100% first year capital allowances will be available to anyone investing in a range of approved products - which currently include electric motors and variable speed drives.
For instance, anybody purchasing a variable speed drive (VSD) from a list of qualifying VSD manufacturers will be able to claim ECA allowances on the cost of the drive plus any capital costs incurred in its installation.
References: (1) www.environment.detr.gov.uk/climatechange.vcclevyeea (2) www.eletricity.org.uk/uk_inds/pricesla.html (3) "Reducing Vacuum Costs" Environment Technology Best Practice Guide, GG101 (4) To arrange a free system analysis in the UK, or to discuss other aspects of the CCL, contact Gary Davenport on 01622 716816 or email gary.davenport@rietschle.co.uk (5) www.eca.gov.uk
