The Difference Between Energy Star, Energy Guide and Enervee
You are probably familiar with the blue Energy Star certification and yellow EnergyGuide label and are wondering where Enervee fits in? First let's look at the problem.
In March, the American Council for an Energy Efficient Economy released a report on energy efficiency labels that sums up the problem well:
Key data available to consumers—including average energy prices, estimated annual cost information, comparison scales, and usage assumptions—often lag far behind changes in the market and can be very misleading to purchasers.
American Council for an Energy Efficient Economy (ACEEE) Research Report E136, March 2013
In the above example, we are looking at an Energy Star qualified Whirlpool refrigerator. The EnergyGuide label shows an annual energy cost of $67 where as it could be as low as $40 if you live in Seattle, Washington or as much as $235 in Maui, Hawaii. In addition, the yearly cost is not as helpful as knowing the total energy cost you will have to pay over the lifetime of the product (14 years for Fridges). Your true energy cost would be $557 in Seattle or $3,286 in Maui.
Solution: The Enervee Score
Enervee solves this problem with the Enervee Score, a MPG (miles per gallon) rating with coverage of all appliances, providing an energy efficiency rating based on real time data. It was designed to be easily embedded on any online shopping comparison site or mobile app and can also be triggered via a QR code lookup at retail store locations.
The Enervee Score is a 0 to 100 (best) rating that is dynamically calculated by comparing the energy consumption and capacity of a product (i.e. size, volume, or processing speed). We have broken the score into four energy efficiency levels: less (1 to 25), somewhat (26 to 50), fairly (51 to 75) and very (76 to 100). This easy scoring methodology helps you to quickly identify the best products via a comparison of thousands of appliances and electronics across 30 different product categories, such as TVs, Refrigerators, Freezers, Washing Machines, Dryers, Dishwashers, ACs, etc. The Enervee Score is updated daily and seamlessly integrated with the product listing to enable sorting or filtering on energy efficiency and cost while shopping. In addition, it provides an easy way for you to know how energy efficient you are based on the products you have at home.
Let’s take a look at how we actually calculate the Enervee Score. We first determine an efficiency factor for each product based on its amount of capacity per watt of energy consumed, taking into account the electrical losses of the underlying product components. The higher the efficiency factor the better a product is, since that means the product uses less energy for its size, volume, or processing speed. For each category, the 50 mark or middle of the scale, is defined by the new product whose efficiency factor represents the lower end of the energy efficiency scale. We establish this as the point of differentiation between new and old models, since the vast majority of current products are more efficient and therefore using more advanced technology. Any products below this point are "older models" since they do not follow the current efficiency trend.
We then look at the 5% of products with the highest efficiency factor to establish the top end of the scale. You might be curious why we do not just select the product with the absolute highest efficiency factor and use that to establish the 100 point on the scale (most efficient). This is because the Enervee Score is dynamic, meaning that as new products come on the market they are scored on a daily basis. Since the entire scale of the Enervee Score is fully dependent upon the threshold that sets the 100 point of the scale, we do not want this changing drastically if a single new TV has greater efficiency than any other product. Therefore we look at a select group of the top efficiency products to make a determination for the high end of the scale. This ensures that the scale adjusts only when a new efficiency trend is established based on a statistically significant number of products.
Once the scale has been established, we score all products from 0 to 100. In some cases, it is necessary to apply logarithmic scaling to ensure that we accurately account for the wide delta in efficiency factors between products on the low and high end of the scale. While this sounds very technical, all it really means is that we are smoothing the distribution of scores rather than having big gaps between different efficiency levels. Products scoring above 75 are deemed "very energy efficient" as they score in the top 25% of all products in the category. All historical products are also scored using this scale with the result being that the majority receive a score below 50 as they are often "older models".