My visit to Tuvalu is part of a project I am working on to assist with capacity building with the electricity corporation’s fledgling renewable energy and energy efficiency unit which is the unit tasked with driving Tuvalu towards 100% renewable power generation by 2020 – an ambitious goal.
While introduction of renewable energy to take over diesel generation will take time, energy efficiency and management initiatives can assist with that transition – and it is clear that gaining an understanding of what people use their electricity for is vital to identifying opportunities for energy efficiency.
The fridge / freezer, to keep meat fish and other food items (including water), the kettle to boil water to make it safe to drink, fans to keep people cool in the midday heat – even air-conditioners in some buildings – all provide a significant demand on the power system in Funafuti and the outer islands of Tuvalu and require large amounts of diesel to power the generators needed to “keep the lights on”. Which interestingly are mostly tube-fluorescents or compact fluorescents (CFLs) - of varying quality - the humble incandescent light-bulb no longer finds a market in Tuvalu.
Lighting
Not all CFLs are created equal there do appear to be numerous CFLs installed around the various buildings I have visited that really don’t provide the lighting performance once might expect from a similarly rated good quality bulb in NZ, Australia or Europe. And often associated with this poor light output is a lower power factor that affects the overall quality of the power supply and has to be corrected to ensure stability of the grid – at a cost to the generation company.
While there would appear to be some benefit in setting minimum standards for lighting performance, the issue of affordability must be taken into account.
Figure 1 - Compact Fluorescent Bulb in hotel
Refrigeration
With a large proportion of foodstuffs being imported and requiring refrigeration (bulk storage is in freezer containers at the port), most households have a fridge (or two) and the small stores around the villages have 2 or three chest freezers for meat and dairy products in addition to the odd fridge for cold water/drinks.
Refrigeration is a significant load and again minimum energy performance standards should be considered for such products. I have some portable power meters that the client has purchased as a tool for the energy efficiency programme. I have used one of these to monitor the performance of the fridge in my room – interestingly the rated output was 0.33kWh per day (i.e. 0.33 units per day). Over a 24 hour period the actual consumption was more like 0.63kWh – nearly twice the rated output. While I have used the fridge to cool water for drinking (which could explain the extra load) the seals on the fridge are good and I can only conclude that perhaps the rated output is based on the unit being in a cooler climate where the ambient temperature is lower – and therefore the heat loss from the body of the fridge is lower. Food for thought and further analysis...
Figure 2 – Freezer containers at Port - Tuvalu
Water
Another key load is boiling water to make it safe to drink. While most water is rainwater collected from the roof of homes/businesses and stored in tanks, there remains a risk of microbial contamination.
Some folks use gas cookers to boil water then transfer this to large containers to cool and dispense for drinking and cooking, some use electric kettles/urns.
With an abundance of solar radiation and a water supply that is essentially pure (i.e. rainwater) the use of solar stills may be much more appropriate and take a significant load off the local grid. For those who use gas, a solar still would most likely significantly reduce their gas bill (which is a significant saving for those households). 
Disclaimer – the observations and opinions of the author are his own and do not represent the views of his employer, client or the people of Tuvalu.
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