The Eco Kettle was invented, in the UK, by Brian Hartley and designed and developed for the marketplace by Product Creation Ltd
in association with Mass Electrical Co Ltd. Eco Kettle has a patented dual reservoir, one of which holds 1.5 litres of water, along with a measuring button which allows any quantity--from a single cupful to full capacity--to be released into a separate boiling chamber. It "could save consumers 30% of energy compared with their normal kettle". The kettle has a 3kW stainless steel concealed element, a washable limescale filter, and a locking lid. If you're curious about how it operates, an owner's operating guide is located here.
In UK online outlets, prices were found in the neighborhood of £39.95 ($US 68.72). Why could we not simply pour the right amount of water into an ordinary stovetop kettle and save energy without buying more "stuff"? Well, we could; but, the tradeoff is not that simple. When you heat a stovetop kettle you are also heating the shell and handle in addition to the water inside. Additionally, a stove top element leaves residual heat in the resistance coil and its cover tube. These inefficiencies are reduced by using a plug-in electric kettle which is not "cordless". [Chosing a "cordless" plug in kettle, the kind with a removable base, means lowered efficiency.]
The built-in measuring capacity of the Eco-kettle adds convenience and precision. We should hope that the design also provides for an automatic shut off when the water reaches boiling point, and insulation to keep water hot until that phone call is finished. Bundling features is an advantage if it leads to a personal enjoyment that encourages conservation...to a point that is price determined.
We noticed that other electric teakettles, with many features comparable except for the dual reservoir, are priced in the $40 to $70 range. Eco Kettle is on the high end but not unreasonable, in other words.
Conclusion: Eco Kettle could be a good value if you don't have a functioning electric kettle and indeed want one. It does not make sense, however, to replace an existing electric kettle on the theory that the energy savings will make up for the resources needed to produce two electric kettles.