The Boom of Solar lamps: a Blessing For the Environment?

No battery, no fragile bulb, the crank or solar lamp is ideal for hikers, do-it-yourselfers ... But the little question to debate: what is the impact of these lamps on the environment? Of course, we do not consume electricity, Mother Nature or our "muscles" provide for our needs, but our lamp is it "eco-designed "? Is it planned to last?

The composition of the external structure

Solar lamps are usually made of plastic, but which one? PET (or PETE), PP, PE BD, HDPE, PS, ... these symbols are found on our plastic objects, without us really knowing what they mean. The three most used plastics in the consumer industry today are PET, HDPE, and PP.

The fart

Polyethylene Terephthalate. It is often used for soft drink bottles for its transparency, impact resistance, low weight, and impermeability to water, gases, and aromas. If it is currently the most recyclable plastic, a recent Italian study has shown that beyond a certain time of storage of water in a PET bottle, a phthalate probably carcinogenic could develop! Prohibition to put the lamp in your mouth too long!

HDPE

Polyethylene High Density, which represents 50% of the market and is found in bottles of detergents, adhesive films, trash bags, toys, pipes. It is opaque or translucent, rigid, impact resistant, waterproof, impervious to grease and barrier to chemicals. There are bacteria in nature that are capable of degrading polyethylene macromolecules, but they can only do so by taking one end and it is understandable that it will take time to degrade entities that include to 100,000 monomeric units. For plastic bags, one of the possible solutions is to include "elements" easily attackable by bacteria (pieces of starch chain for example).

The PP

Polypropylene mainly presents in harder objects such as plastic dishes, reusable food containers, water bottles, margarine packaging ... Low density (about 0.95), it combines chemical, thermal and electrical properties. It is currently not recyclable outside the industry. And it's usually the one used in lamps!

Internal circuits

The electronic circuits that are contained in the solar garden lights imply that your lamp once failed will become a WEEE (Waste Electrical and Electronic Equipment), thus a hazardous waste for the environment. Indeed these circuits include toxic elements. It is estimated that each French produces each year 14 kg of waste of this type (not just lamps, but all confused refrigerator, washing machine, televisions, computers, toaster, drill ...) and the total amount produced increases by 4 % each year, a growth rate much higher than that of all household waste. So be careful where you throw it.

The lightbulbs?

It is essential to favor LEDs or LEDs in French (light-emitting diode). Indeed they have excellent mechanical resistance to shocks, crushes, and vibrations. Their lifespan is much longer than a conventional incandescent lamp or even a fluorescent lamp (50,000 to 100,000 hours against 6,000 to 15,000 hours for fluorescents and a maximum of 1,000 hours for lamps incandescent). The only drawback is that LED lamps have a purchase price that is two to four times higher than that of conventional lamps, at equal brightness, but this trend should decline rapidly given the rapid growth in sales.

The batteries?

The recharging by solar energy is clean and inexhaustible, but not the battery which remains to renew. Again, the question of whether it is recyclable should be addressed. In addition, you should know that the presence of a battery is not essential. Indeed there are models of the flashlight to shake that frees you batteries and batteries to change. It is a hybrid capacitor technology that allows up to 100,000 recharges (by comparison a dynamo lamp running on battery is limited to 500 recharge cycles). But stay the capacitor ...

But what is the place of lamps in the world?

Often seen as a gadget in our societies, we must know that lamps remain for two billion people, their only means of lighting, reflecting precarious living conditions. A kerosene lamp illuminates badly, is a source of respiratory problems, burns even fire, emits a lot of CO2 and is expensive to use (oil price). Electric lighting provides comfort and security desired by the people. The challenge is to succeed in the oil / solar transition on a large scale and in a sustainable way. From an ecological point of view, the use of oil lamps in the world would represent each year 50 billion liters of oil or 130 million tons of CO2.

International organizations such as the UN and the World Bank are running various programs to encourage this oil / solar transition.

Notes

Ecodesign is the consideration and reduction of the impact on the environment from the product design. It is a preventive approach that is characterized by taking into account the entire life cycle of the product (from the extraction of raw materials to its disposal as waste) and all environmental impacts (consumption of raw materials, water, and energy, discharges, waste production.