Tuesday, 12 July 2016

The Smart Home

A smart home is one in which the various electric and electronic appliances are wired up to a central computer control system so they can either be switched on and off at certain times (for example, heating can be set to come on automatically at 6:00AM on winter mornings) or if certain events happen (lights can be set to come on only when a photoelectric sensor detects that it's dark).
 These devices communicate with each other on your home network or via Bluetooth, doing things like sharing information, transferring files and digital media and providing remote access and control for domestic appliances.
Many connected home devices such as heating, lighting and security systems can be controlled remotely by a smartphone, tablet or computer, typically via an app.
 The most common connected devices are computers, games consoles and Smart TVs, but over the last few years the number and type of connected devices has expanded to include connected heating systems, lights, kettles, vacuum cleaners, scales and security cameras.
Accessories that can connect to the internet such as locks, door sensors and even babies’ dummies can be smartphone-controlled and typically use Bluetooth to connect to your smartphone.
Collectively, these devices are part of the Internet of Things.
 Many connected home devices can also be controlled remotely. Connected heating systems such as Nest’s Protect or British Gas’s Hive allow you to turn your heating on and off remotely using a phone, so if you get back home late one night you don’t waste money heating your house while you are away.
Connected home devices can also work together. Nest’s system includes a thermostat and the Nest Protect smoke/carbon monoxide detector, and if the latter detects a carbon monoxide leak, it will communicate with the thermostat to turn the heating off.
America is slightly ahead of the UK in terms of connected-home technology, Amazon Echo, an internet-connected hub that works with Alexa, a cloud-based voice system that can respond to voice commands.
Echo and Alexa work with smart home gadgets made by other companies. Using their voice, Ford owners can lock/unlock their car doors, Philips Hue users can dim their home lights or Nest owners can adjust the thermostat temperature.
If you're elderly or disabled, home automation systems like this can make all the difference to your quality of life, but they bring important benefits for the rest of us as well. Most obviously, they improve home security, comfort, and convenience. More importantly, if they incorporate energy monitors, such as thermostats, or sensors that cut the lights to unoccupied rooms, they can help you reduce household energy bills; automated systems such as Bye Bye Standby, which cut the power to appliances when they're not being used, can dramatically reduce the energy wasted by appliances such as washing machines, dishwashers, and TVs when they're not actually being used.

Friday, 4 September 2015

Slashing household solar subsides will kill off industry

The government wants to slash by 87% subsidies for householders who install solar panels on their rooftops, in a move that renewable energy experts warn could kill off a promising industry.
The potential reductions in the level of feed-in tariff (FIT), contained in a long-awaited consultation document released by the Department of Energy & Climate Change (Decc), and are far larger than expected.
The assault on solar power comes after ministerial decisions to remove financial aid from new onshore wind farms and slash home energy efficiency measures. There is even speculation that Decc could be wound up as a standalone department.
From 1 January, ministers are proposing reducing the feed-in tariff for smaller scale solar installations from 12.47p per kilowatt hour to 1.63p with large standalone units eligible for subsidies of 1.03p per kWh, compared with 4.28p today.
The government has blamed concerns that the £7.6bn budget for renewables will be drastically overspent, and argues that solar and onshore wind should be able to largely support themselves.

Tuesday, 11 August 2015

Solar PV Still Cost Effective

A 4kWp system can generate around 3,800 kilowatt hours of electricity a year in the south of England – roughly equivalent to a typical household's electricity needs. It will save nearly two tonnes of carbon dioxide every year. A 4kWp system in Scotland can generate about 3,200 kilowatt hours of electricity a year – more than three quarters of a typical household's electricity needs. It will save more than a tonne and a half of carbon dioxide every year.
System size
Feed-in-Tariff generation payment (£/year)
Feed-in-Tariff export payment (£/year)
Electricity bill savings (£/year)
Carbon dioxide savings (kgCO2/year)
Valid between 1st April - 30th June 2015Valid between 1st July - 30th September 2015
London, South England4kWp£510£495£90£1351,870 kg
Aberystwyth, Wales4kWp£480£460£85£1251,750 kg
Manchester, North England4kWp£450£435£80£1201,650 kg
Stirling, Scotland4kWp£425£410£75£1101,560 kg
The average domestic solar PV system is 4kWp and costs £5,000 - 8,000 (including VAT at 5 per cent). 
When Fits (Feed-in Tariff ) were first launched in 2010, a typical large domestic photovoltaic system cost £15,000-£18,000 to install. Early adopters were promised 41.3p per kilowatt hour (kWh) generated for 25 years, plus generous savings on their electricity bills worth up to £160 a year. Incomes and savings of more than £30,000 were promised for a £15,000 investment.

Price falls in PV panels over the past five years mean that the same system can now be installed for £5,000-£6,000 – and the government has responded by cutting the income paid accordingly. Those installing a system before 30 September this year now receive 12.92p per kWh if they live in a home that is energy performance certificate band D or above.
You still need a south facing, unshaded roof, ideally at a 45-degree pitch. Those who live in the south will get the highest income. Someone installing a £6,000 panel system on such a roof in Hertfordshire can expect an income and electricity bill savings of around £600 a year. Payments are index linked and are guaranteed for the next 20 years.
For an accurate calculation of how much your roof will generate use the EnergySavingsTrust calculator.

Tuesday, 4 August 2015

Apple's HomeKit

The first products to take advantage of Apple’s smart home technology were unveiled today, just days before the start of the company’s Worldwide Developer Conference.

Five device makers announced products that dim the lights or adjust room temperature with a spoken command or control fans and other home appliances from the iPhone, iPad or iPod touch. Two products are available now, with others reaching stores in the coming weeks.
IHome, a maker of iPhone- and iPod-compatible clock radios and audio accessories, said its first HomeKit product would begin reaching stores in late June. Its SmartPlug allows consumers to use Siri to control their lighting, fans and other home devices.
Lutron Electronics’ Cas├ęta Wireless Lighting Starter Kit provides wireless plugs, remote control dimmer switches and a smart bridge, which allows homeowners to adjust their lights (and, in some cases, the window shades and thermostats) without leaving their couches. Its software will even send a notification if the homeowner has left without turning off the lights. It is available now.

Toronto-based Ecobee announced that its wireless thermostat now works with HomeKit, allowing users to adjust their heating or cooling using Siri on their iPhone or iPad, while Insteon’s HomeKit-compatible hub lets consumers control a range of home gadgets, from door locks and garage door openers to lightbulbs. HomeKit is on sale today online.
HomeKit is a system for connecting smart home devices through iOS.
Apple allows for either WiFi or Bluetooth low energy (LE)-enabled devices to get certified as a HomeKit accessory. Apple is requiring device makers using both WiFi and Bluetooth LE to use complicated encryption with 3072-bit keys, as well as the super secure Curve25519, which is an elliptic curve used for digital signatures and exchanging encrypted keys.
“These security protocols are bleeding edge,” said Diogo Monica, a security lead at Docker and an IEEE security expert.
WiFi-enabled devices can handle these security requirements, but it seems devices running over Bluetooth LE are having some issues. The intensive processing demands for generating and sending these security keys is what’s likely causing these lag times.

Such lag times render many of these devices useless. For example, a smartlock that makes its user wait 40 seconds before it opens is clearly inferior to a traditional lock. One of HomeKit’s selling point is that it provides a more reliable user experience, so these kinds of lag times will need to be sorted out before Apple can become a major platform for the smart home.

People with an August smart lock fitted to their front door can now use an Apple Watch to lock and unlock their home with 'just a swipe and a tap'.
The watch app also tells users who has recently come and gone as well as receiving a notification when someone enters of leaves their house.
The August lock is made of 'durable anodized aluminium' and can be managed using the app which works on a smartphone and Apple Watch, as well as online.
Owners of the lock, created by technology entrepreneur Jason Johnson and industrial designer Yves Behar, can already lock and unlock their door with their iPhone, but the watch will make the process more convenient, because the 'digital key' is already on their wrist.
The battery-operated lock, which launched last year, costs $249 (£160) and its makers claim, takes just 10 minutes to install.
It includes deadbolt adapters and faceplates that work with around 90 per cent of locks on the market in the US.
The encrypted locking technology issues registered devices such as smartphones or the Apple Watch, or invited devices, with unique codes that can't be copied.