Power saving for healthcare facilities
Dialysis, on an individual patient basis, is a power-hungry process. As electricity costs rise, additional financial burdens will accrue to haemodialysis facilities.
The power requirements of a standard single-pass system providing 3 x 4 – 4.5 hour dialysis treatments/week, plus the power required to create sufficient RO water to generate enough dialysate to supply those 3 treatments is approximately half the weekly power requirements of an average 4 person Australian home in 2011 (8,9,10).
Every two dialysis patients, in every dialysis session, are a ‘power-soak’ equivalent to the daily use of an average suburban household.
All services should critically seek to lower their power consumption, and its associated costs…
There are two primary steps to consider:
- Reduce excess power use.
- Consider renewable power-assisted options… e.g: solar power.
Reducing power consumption
The problem with power consumption is that many of the steps required to reduce excess use (power wastage) appear fiddly, petty … even insignificant. They annoy us, and seem like an inconvenience.
However, most energy experts maintain that the set-up costs of power-reduction systems are soon recouped from power bill savings. Watch TV, or read the advertising leaflets … they all spread the same message.
Regardless of the added costs of a home dialysis system, if we all take a critical look at our own homes, we will soon realize the power that is used in lighting, in heating and cooling, by computers, TVs, and appliances – of which all, or most, remain ‘switched on’ or in ‘stand-by’ mode, 24 hours a day. This applies, whether the equipment is in use or not.
Then, for a home dialysis patient, add in the power requirements of the dialysis machine and RO. Add the fact that most home patients who choose home dialysis do so to access extended hour and high frequency dialysis regimens – regimens that use far more power than centre-based care – and power costs can soar.
So, be smart and start organizational campaigns to reduce the unnecessary power usage by switching off appliances, computers and non-essential equipment when not in use. See 10:10 campaign
Though most current dialysis machines are now fitted with heat exchangers – inbuilt systems that heat the incoming fresh dialysis fluid by heat exchange with the outgoing spent dialysate – ensure that this is the case via your manufacturer.
If not, heat exchangers can be retro-fitted. The NHS in the UK has recently retro-fitted heat-exchangers right across all dialysis programs, simply to reduce power consumption and increase system efficiency (11). If exchangers are not fitted, they can be – and your manufacturer should ensure that this is done.
Data from Fresenius Medical Care in Germany suggests that up to 20% of all dialysis unit power is used for lighting (2).
Japanese researchers have recently reported that light – especially fluorescent light = the most common light source used in dialysis services worldwide – may be detrimental to exposed blood (12) … e.g. the extracorporeal circulation during repeated dialysis.
They have shown that reactive oxygen species are activates in extracorporeal circuits exposed to fluorescent light and, by induction of endothelial injury, can lead to nitric oxide pathway activation with widespread metabolic consequences.
Further research into the potentially harmful effects of light has not yet been performed but, if the Japanese work is confirmed, blacked-out extracorporeal lines or the replacement of fluorescent lighting with LED lighting wherever possible may become a future dialysis imperative.
Sensible power reduction: the installation of motion or time sensor switches for lighting, computers and other non-essential electrical equipment, is a simple step that few (if any) have as yet taken.
Considering alternative power-assisted Haemodialysis
There is now some limited trial data surrounding the use of solar panels to augment the power requirements of haemodialysis (7). This model offers an alternative power-augmenting system for dialysis facilities.
As electricity prices rise and CO2 taxes and levies are debated and/or introduced, power costs will loom larger for healthcare organizations, especially if utility rebates lag or diminish. In addition, any energy sourced from “green” power options alleviates the carbon burden of non-renewable energy sources, e.g. coal.
How to work out your haemodialysis unit solar power requirements?
- Apply a standard industrial power-meter to your dialysis equipment – both dialysis machine and reverse osmosis system.
- Measure their average hourly power draw (kWh).Perform several measurements on several machines and mean the data.
- Determine the daily average solar insolation at the latitude and longitude of your unit or patient home, using the following method: Go to: http://www.wunderground.com/calculators/solar.html
- Enter your city (e.g. Geelong) and country (e.g. Australia).
- Check the ‘Give raw insolation data’ box Scroll down to ‘Submit’, and click.A graph will appear, showing the raw monthly insolation data for your location (e.g. Geelong) in kWh/m2/day.
- The average kWh/m2/day is then calculated for you (e.g. Geelong = 6 kWh/m2/day).This means that each m2 of solar panel will generate ~6 kWh/day power.
- Select a ‘panel model’ … NB: a number of potential solar arrays are modelled at this Internet site.
- In addition, check your local solar power suppliers for their range of products, and apply.
o The ‘generative efficiency’ is then automatically determined.If the chosen/preferred array is unlisted, (NB: the array used for the Barwon Health trial was a Conergy 175), the efficiency rating for that array can be supplied by the chosen manufacturer.
Finally, a predicted potential cost/benefit outcome can be calculated, based on power requirements, array size, installation cost, and any locally applicable rebate or pay-back arrangements.
If solar power isn’t an option for your facility, then consider how else you might be able to augment your power needs with an alternative, renewable power source applicable to your area (wind, geo-thermal, or hydroelectric).
Alternatively, question your power supplier re the % of power drawn from alternative power sources (ie solar, wind, geo-thermal or hydroelectric).
Shop around. You might be surprised at both the differences in price, and the % of power your company offers from “green” power sources.