Sustainable energy/ja: Difference between revisions

<div lang="en" dir="ltr" class="mw-content-ltr">

====Transport====

[[File:Hornby Street Separated Bike Lane.jpg|thumb|right|alt=Group of cyclists using a bike lane in Vancouver, Canada|[[Utility cycling]] infrastructure, such as this [[bike lane]] in [[Vancouver]], encourages sustainable transport.>]]

{{main|Sustainable transport}}

Transport accounts for 14% of global greenhouse gas emissions, but there are multiple ways to make transport more sustainable. [[Public transport]] typically emits fewer greenhouse gases per passenger than personal vehicles, since trains and buses can carry many more passengers at once. Short-distance flights can be replaced by [[high-speed rail]], which is more efficient, especially when electrified.

The [[Energy efficiency in transport|energy efficiency of cars]] has increased over time, but shifting to [[electric vehicle]]s is an important further step towards decarbonising transport and reducing air pollution. A large proportion of traffic-related air pollution consists of particulate matter from road dust and the wearing-down of tyres and brake pads. Substantially reducing pollution from these [[Non-tailpipe emissions|non-tailpipe]] sources cannot be achieved by electrification; it requires measures such as making vehicles lighter and driving them less. Light-duty cars in particular are a prime candidate for decarbonization using [[Electric battery|battery technology]]. 25% of the world's [[Carbon dioxide|{{CO2}}]] emissions still originate from the transportation sector.

Long-distance freight transport and aviation are difficult sectors to electrify with current technologies, mostly because of the weight of [[Electric vehicle battery|batteries]] needed for long-distance travel, battery recharging times, and limited battery lifespans.  Where available, freight transport by ship [[Rail freight transport|and rail]] is generally more sustainable than by air and by road. [[Hydrogen vehicles]] may be an option for larger vehicles such as lorries. Many of the techniques needed to lower emissions from shipping and aviation are still early in their development, with [[ammonia]] (produced from hydrogen) a promising candidate for shipping fuel. [[Aviation biofuel]] may be one of the better uses of bioenergy if emissions are captured and stored during manufacture of the fuel.

<div lang="en" dir="ltr" class="mw-content-ltr">

====Buildings====

{{Further|Renewable heat|Green building|Zero-energy building}}

Over one-third of energy use is in buildings and their construction. To heat buildings, alternatives to burning fossil fuels and biomass include electrification through [[heat pumps]] or [[Electric resistance heater|electric heaters]], [[Geothermal heating|geothermal energy]], [[central solar heating]], reuse of [[waste heat]], and [[seasonal thermal energy storage]]. Heat pumps provide both heat and air conditioning through a single appliance. The IEA estimates heat pumps could provide over 90% of space and water heating requirements globally.

A highly efficient way to heat buildings is through [[district heating]], in which heat is generated in a centralised location and then distributed to multiple buildings through [[insulated pipe]]s. Traditionally, most district heating systems have used fossil fuels, but [[District heating#Fourth generation|modern]] and [[cold district heating]] systems are designed to use high shares of renewable energy.[[File:Aghazade mansion.jpg|thumb|alt=Building with windcatcher towers|[[Passive cooling]] features, such as these [[windcatcher]] towers in Iran, bring cool air into buildings without any use of energy.]]Cooling of buildings can be made more efficient through [[Passive solar building design|passive building design]], planning that minimises the [[urban heat island]] effect, and [[district cooling]] systems that cool multiple buildings with piped cold water. [[Air conditioning]] requires large amounts of electricity and is not always affordable for poorer households. Some air conditioning units still use [[refrigerant]]s that are greenhouse gases, as some countries have not ratified the [[Kigali Amendment]] to only use climate-friendly refrigerants.